Cannabis & Cannabinoids · Terpenes · The rose-like aroma molecule in rose and geranium oils, lemongrass and cannabis

Geraniol

(2E)-3,7-dimethylocta-2,6-dien-1-ol (geraniol), C10H18O · also called Geraniol, geranyl alcohol, trans-geraniol; the cis partner is nerol

Geraniol is a rose-smelling plant molecule (a terpene alcohol). It is a major part of some rose, geranium and lemongrass-type oils, and cannabis makes tiny amounts of it. Almost all research on pure geraniol is in mice, rats and cells. The only human trials are two small studies of a special gut supplement. Geraniol that has sat in air can cause skin allergy.

General information, not medical advice. Last substantive update October 25, 2026 · Not medically reviewed. A named clinician has not signed off on this page. How this page is made

About Geraniol

Geraniol is a rose-smelling terpene alcohol made by rose, geranium and some lemongrass-type plants, and by cannabis in tiny amounts. Almost all research on the pure molecule is in mice, rats and cells: cannabinoid-like activity, pain thresholds, anxiety-like behaviour and, in the lab, cancer cells. The only human trials are two small studies of a gut-targeted supplement for irritable bowel syndrome. Skin allergy is the best-documented harm: geraniol that has reacted with air forms allergens, and 3% to 8% of dermatitis-clinic patients reacted at the patch-test strengths used. In our lab data geraniol is a trace terpene (18 strains, single batches). No source read shows that geraniol changes how THC feels.

What it is

Geraniol is a monoterpenoid: a molecule of ten carbon atoms with the formula C10H18O (PubChem compound 637566). Like linalool, it is an alcohol. Its cis partner is nerol. When geraniol meets air or skin enzymes it turns into the aldehydes geranial and neral, which together are called citral and are the allergens behind most geraniol allergy.

In plants geraniol is a starting molecule for other compounds, such as the iridoid terpenes. We did not find a source that says which enzyme makes it in cannabis. In people, geraniol is broken down in hours: in three volunteers about half of an oral dose came out in urine as acid metabolites within 72 hours.

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Where you meet geraniol

Rose, geranium and some grass oils are the best-known sources. Two rose oils from Indian hills were 8.3% to 30.2% geraniol (2011), and it was one of three main parts of most rose waters tested in Iran, where some products had been adulterated with other oils (2014). One rose-scented geranium oil was 14.6% geraniol (2023). In a Nepal study, geraniol was reported at 37.1% in one citronella oil fraction and at 76.6% in lemongrass leaf oil, but the authors say citral is normally the main compound in these grasses, so these look like single unusual samples. Amounts vary by plant, part, site and batch.

Geraniol is also a common ingredient in perfumes, cosmetics, cleaners and candles, and an estimated 1.43 mg a day was found in the urine of ordinary adults. The pages for rose, geranium, lemongrass and citronella oils are linked below.

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What the lab numbers show

Our lab data hold 20 geraniol measurements for 18 named strains (Hash Plant and Jabberwocky each have two). All come from one published table: the supplementary spreadsheet of Richins and colleagues (2018, PLoS ONE) with 72 commercial medical cannabis flower samples, measured by gas chromatography (GC-FID). Each value is a single batch (one cured flower sample) and the test dates are not reported. The table column is headed "% dry wt", but the numbers look like mass fractions rather than percentages (the same table shows Δ9-THC at about 0.263) and the unit was not independently verified, so we quote the numbers as printed and make no unit conversion. The printed values run from 0.0000657 (Grape Stomper) to 0.000486 (Lucky Charms). That is a very small amount compared with the main cannabinoids in the same table.

The highest printed values were Lucky Charms (0.000486), Rocket Fuel (0.000400), Jabberwocky (0.000379), Hash Plant (0.000357) and Venom OG (0.000321). The lowest were Grape Stomper (0.0000657), Rosetta Stone (0.0000725), Chemdawg #4 (0.0000737), Purple Eclipse (0.0000800) and Skywalker OG (0.0000938). Only one of the 28 strains with a profile page here has a value: Gorilla Glue #4, 0.000270 (one batch). The same strain name varies a lot between samples: the two Jabberwocky samples were 0.000379 and 0.000114 (more than threefold apart) and the two Hash Plant samples 0.000357 and 0.000225. These numbers are measurements of flower content from a published table, not from our own testing. They say nothing about effects, and we have no geraniol measurements from regulator datasets or in other units, so numbers from other sources must not be compared with these.

The popular claims

"Geraniol makes cannabis calming or relieves pain." No source read supports this in people. In mice, injected geraniol (200 mg/kg) raised pain thresholds, but cannabis flower holds only trace amounts of it in our data. No human study tested geraniol with THC.

"Geraniol fights cancer." It does not treat cancer. The evidence is cancer cells in dishes and mice, and the concentrations used in dishes are far above what the body reaches (blood geraniol peaked at about 0.05 micrograms/mL after a 200 mg/kg oral dose in mice).

"Geraniol is a proven mosquito repellent." Results are mixed: one candle test favoured it, and a 2% spray on ponies did not give a significant effect.

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What the research shows

Human: one double-blind trial in 56 adults with irritable bowel syndrome found a lower symptom score after 4 weeks on a low-absorbable geraniol supplement than on placebo (195 versus 265), with 52.0% versus 16.7% responding, and a before-and-after pilot also found lower scores. Two authors founded the company behind the supplement. Human landing tests found geraniol candles repelled mosquitoes better than citronella candles.

Animals and cells: pain, anxiety-like behaviour, seizures, brain protection, diabetes, psoriasis-like skin, cancer cells and MRSA biofilm. Everything here is laboratory or animal research, mostly at high doses, and no review we read gave a GRADE rating.

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At a glance

Traditional uses history, not proof

Rose water, made by distilling rose petals, is used in Iran in religious ceremonies, food and pharmaceuticals (a 2014 paper)
Fragrance and flavour ingredient in perfumes, cosmetics, cleaners and food (reviews; US FDA list)
Rose, geranium, citronella and lemongrass oils in aromatherapy and as insect deterrents (modern use)
Ingredient in some natural mosquito repellents (a 2010 paper)

Studied for research

Pain thresholds in mice: strongest of four cannabis terpenes in two mouse studies, very low; no human data
Cannabinoid-like activity in mice and cells, insufficient
Anxiety-like behaviour in rats, seizures and stroke-like injury in rodents, very low or insufficient
Irritable bowel syndrome: one 56-person trial and one pilot of a gut-targeted supplement, low
Cancer cells in the lab and in mice, insufficient: laboratory research, not treatment
Diabetic rats, psoriasis-like mouse skin, MRSA biofilm in the lab: very low
Mosquito repellence: one favourable candle test, one non-significant pony test, mixed

Main compounds

Geraniol, C10H18O
Geranial and neral (together citral), the aldehydes that form when geraniol meets air
Metabolites: Hildebrandt acid, geranic acid and a glucuronide form
Relatives: nerol, citronellol, geranyl acetate, linalool
Other cannabis terpenes: linalool, humulene, beta-pinene, caryophyllene, limonene

Common forms

Tiny natural amounts in cannabis flower
Essential oils: rose, geranium, lemongrass-type and citronella
Pure compound in lab, animal and small human studies
A low-absorbable supplement in two small bowel studies
Ingredient in perfumes, creams, household products and candles

Research links: PubChem: Geraniol · US eCFR: 21 CFR 182.60 (flavouring substances) · Patch testing, oxidised geraniol in 1,476 patients (PubMed) · Cannabis terpenes relieve pain in mice (PubMed) · Geraniol for irritable bowel syndrome, randomised trial (PubMed) · Research Library · Genes & Biomarkers Library

What it is and its history

Name: Geraniol ((2E)-3,7-dimethylocta-2,6-dien-1-ol), the trans form. Its cis mirror-partner is nerol.
Chemical name: (2E)-3,7-dimethylocta-2,6-dien-1-ol
Other names: Geraniol; Geranyl alcohol; trans-Geraniol; (E)-Geraniol; (2E)-3,7-dimethylocta-2,6-dien-1-ol; beta-Geraniol; Lemonol; trans-3,7-Dimethyl-2,6-octadien-1-ol
Common names: Geraniol (English); Geraniol (Spanish)
Formula: C10H18O
Molecular weight: 154.25
CAS number: 106-24-1
PubChem ID: 637566
Chemical class: Monoterpenoid (an acyclic terpene alcohol): a small aromatic molecule built from ten carbon atoms that carries an oxygen atom as an alcohol group. Its relatives include linalool, citronellol and nerol; its oxidised forms are the aldehydes geranial and neral (together called citral).
How the plant makes it: Plants build geraniol from the ten-carbon building block geranyl diphosphate. We did not find a source that names the enzyme in cannabis. A 1995 paper says the first step of making iridoid terpenes in some plants is the P450 enzyme geraniol/nerol 10-hydroxylase, which uses geraniol (or nerol or citronellol) as a starting molecule. Cannabis stores terpene-rich resin in glands on the flower, but the sources read for this page do not say where or how it makes geraniol.
Where it is found: Cannabis flower: geraniol was measured in 18 named strains in one published table of 72 commercial samples; values were very small. See "What the lab numbers show".; Rose oil and rose water: geraniol was 8.3% to 30.2% of two Rosa damascena oils from Indian hills, and 3.3% to 6.6% of rose water volatiles in the same study (2011). It was one of three main constituents of most rose waters from Shiraz, Iran (2014), and a named significant part of another rose oil that was mainly phenylethyl alcohol (70%).; Rose-scented geranium (Pelargonium graveolens): geraniol was 14.6% of one oil, with beta-citronellol 29.7% (2023).; Citronella and lemongrass oils: a 2023 Nepal study reported geraniol at 37.1% in one fraction of citronella oil and at 76.6% in lemongrass leaf oil and 87.9% in lemongrass root oil, while saying citral is normally the predominant compound in Cymbopogon oils. Treat these as single samples.; Palmarosa oil (Cymbopogon martini): leaf oil was mainly neral (36.1%) and geranial (53.1%) in the Nepal study; the abstract gives no geraniol figure for it.; Everyday products: described as widely used in cosmetics, personal care products and household cleaners and as a food additive (a 2023 human metabolism paper).
Related or similar compounds: Name: Nerol; Note: PubChem CID 643820, C10H18O. The cis (Z) isomer of geraniol; it appears next to geraniol in rose oils.; Name: Citral (geranial and neral); Note: PubChem CID 638011 (geranial/citral) and 643779 (neral), C10H16O. Aldehydes that form when geraniol meets air or is changed by skin enzymes; common skin allergens.; Name: Citronellol; Note: PubChem CID 8842, C10H20O. A closely related alcohol that is often the main part of geranium and rose oil.; Name: Geranyl acetate; Note: PubChem CID 1549026, C12H20O2. The acetate ester of geraniol.; Name: Linalool; Note: PubChem CID 6549. An isomer of geraniol (also C10H18O) with a lavender-like smell; see the linalool page.

Traditional use and history history, not clinical proof

Tradition or era	Documented use	Source
Rose water in Iran	A 2014 paper says rose water (golab), made by distilling Rosa damascena, is used in Iran in religious ceremonies, food and pharmaceuticals, and is also faked with other oils and synthetic essences.	Moein et al 2014 (PubMed 24863280)
Perfume and flavour industry	A 2020 review describes geraniol as a monoterpenic alcohol with a pleasant rose-like aroma used commercially in cosmetic and household products. A 2019 review notes that the limited plant supply cannot meet the flavour and fragrance industries' demand, so production by biotechnology is being developed.	Maczka et al 2020 (PubMed 32708169); Lei et al 2019 (PubMed 30308694)
Insect-repellent candles and sprays	Geraniol is a US EPA minimum-risk pesticide ingredient according to a 2010 pony study, and was tested in 5% candles in a 2008 field test.	Reeves and Miller 2010 (PubMed 21033064); Muller et al 2008 (PubMed 18437831)
Cannabis terpene research	Geraniol was among the cannabis terpenes tested for cannabinoid-like effects in mice by one laboratory group from 2021 to 2025. No older history of geraniol in cannabis was found in a source read.	LaVigne et al 2021 (PubMed 33859287)
Wikipedia-only claims	Claims that geraniol was first isolated by a named chemist in a named year were not read in a source and are NOT VERIFIED; they are not stated on this page.	none

History shows how a substance was used or discovered. It does not show that a product works or is safe today.

What is inside, and how it may work

What it contains and how those compounds act in cells and animals. Laboratory and animal mechanisms are not proven effects in people.

Main compounds

Compound	Family	Where it is concentrated	Activity studied	Level of evidence
Geraniol PubChem 637566	Monoterpenoid alcohol	Rose petals (rose oil and water), geranium leaves, Cymbopogon grasses (citronella, lemongrass, palmarosa) 8.3% to 30.2% of two rose oils; 14.6% of one geranium oil; see Occurrence for grasses. Cannabis: very small amounts in our lab data.	Studied in animals and cells for pain, anxiety-like behaviour, seizures, cancer cells, diabetes, inflammation and microbes; the only human trials are two small IBS studies of a supplement. ^{40 17 4 29 19}	Mixed
Geranial and neral (citral) PubChem 638011	Monoterpenoid aldehydes	Lemongrass and other Cymbopogon oils	Formed when geraniol oxidises or is changed by skin enzymes; the main allergens behind geraniol allergy. Citral allergy was 2.9% in one patch-test series. ^{8 9 14}	Moderate
Geranic acid and Hildebrandt acid (metabolites) PubChem 5275520	Monoterpenoid acids		The main geraniol metabolites in human urine: Hildebrandt acid 34.4% and geranic acid 12.7% of the dose. The CID given is for geranic acid. ^{16 23}	Low
Citronellol PubChem 8842	Monoterpenoid alcohol	Rose and geranium oils 15.9% to 35.3% of two rose oils; 29.7% of one geranium oil	Often travels with geraniol in rose and geranium oils; not covered further here. ^{40 17}	Insufficient
Nerol PubChem 643820	Monoterpenoid alcohol	Rose oils 4.0% to 9.6% of two rose oils (2011)	The cis isomer of geraniol; reviewed together with geraniol for anticancer effects in cells. ^{40 33}	Insufficient
Linalool PubChem 6549	Monoterpenoid alcohol	Lavender, coriander, cannabis	A cannabis terpene tested alongside geraniol in the same mouse studies; the more studied relative. See the linalool page. ^{19 32}	Mixed

Mechanisms, receptors and pathways

Target or pathway	Gene or receptor	What was found	Level
CB1 receptor	Cannabinoid receptor 1	In cell experiments geraniol and the other cannabis terpenes tested activated the CB1 receptor. In mice geraniol produced cannabinoid-like behaviours that were partly blocked by cannabinoid or adenosine receptor blockers. ¹⁹	Laboratory research
Adenosine A2A receptor	Adenosine receptor A2A	Pain relief from geraniol and other terpenes in mice was blocked by the A2A blocker istradefylline, and spinal cord knockdown of the receptor removed the effect. Cell and computer studies suggested the terpenes are agonists at the receptor. ^{32 31}	Animal research
GABA signalling	GABA, GAD65, GAD67, GABA-A receptor alpha-1 (expression)	In nerve cells and in mice with chemical seizures, geraniol raised GABA and the genes for its making and lowered NMDA receptor 1 and GABA transporters. ⁴²	Animal research
KV1.3 potassium channel	KV1.3	Geraniol reversibly blocked KV1.3 currents in HEK293T cells with an IC50 of about 490 micromolar (a high concentration) and lowered cytokine release from activated human T cells. ⁴¹	Laboratory research
Cell death and cell-cycle proteins (cancer cell lines)	Bax/Bcl-2, beta-catenin, miR-21/PTEN	In prostate, gastric and breast cancer models geraniol raised cell-death signals, arrested the cell cycle and changed Wnt/beta-catenin and miR-21/PTEN signalling. Laboratory and mouse work only. ^{18 43 6}	Laboratory research
Skin allergy: protein binding of oxidation products	Skin enzymes CYP1A1, CYP3A5, CYP2B6	Geraniol is turned by air and by skin enzymes into geranial, neral and epoxides that bind skin proteins and cause allergy. Geranial and neral are separate haptens. ^{8 9 14}	Laboratory research
Bacterial biofilm	MRSA virulence genes (staphyloxanthin, autolysins)	Geraniol downregulated genes involved in MRSA biofilm formation and virulence, and cut biofilm in the lab. ⁷	Laboratory research

Absorption, metabolism and elimination

Absorption: Oral, mice and rats: absolute oral bioavailability of 50 mg/kg was 92% for emulsified geraniol and 16% for fibre-adsorbed geraniol in rats. In a human intestinal cell model, permeability coefficients were 13.1 x 10-3 cm/min from gut side to blood side and 2.1 x 10-3 cm/min the other way. Mouse blood geraniol peaked at only 0.05 micrograms/mL one hour after 200 mg/kg by mouth because it is converted so fast. Human oral absorption was not measured directly; urine metabolites after 25 mg and 250 mg doses in three people showed 41.7% to 55.5% of the dose recovered as four metabolites.
Distribution: In rats geraniol reached the cerebrospinal fluid (0.72 to 2.6 micrograms/mL within 60 minutes). In mice geraniol was found in liver and brain, and geranic acid in kidney, liver, lung and brain.
Metabolism: In humans the main urinary metabolites were Hildebrandt acid (34.4 +/- 5.6% of the dose) and geranic acid (12.7 +/- 5.6%), with smaller amounts of 3-hydroxycitronellic acid (2.2%) and 8-carboxygeraniol (0.19%, the only specific marker). In mice a glucuronide conjugate of geraniol was found at higher levels than geraniol. In skin-like enzyme mixes geranial was the main product.
Elimination: Peak urinary metabolite levels came 1 to 5 hours after the oral dose and half-lives were about 2 to 4 hours (three volunteers). Intravenous geraniol in rats had a blood half-life of 12.5 +/- 1.5 minutes. An estimated average daily intake from 41 urine samples of adults without work exposure was 1.43 mg.
Bioavailability: Human bioavailability is not established. Rats: 92% (emulsified) and 16% (fibre-adsorbed). Inhaled or vaped geraniol from cannabis has not been studied.

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11benefits and uses looked at

43studies and sources checked

Low certaintybest evidence rating found

12lab markers tracked in trials

1 mixed findings1 low certainty6 very low certainty3 not enough evidence

What was looked at

The 11 benefits and uses checked for Geraniol, each with how strong the evidence is. Tap one to open it.

Cannabinoid-like activity in mice and cells (laboratory research)Not enough evidence
Pain thresholds in mice (animal research)Very low certainty
Anxiety-like behaviour in rats (animal research)Very low certainty
Seizure-like activity in mice and nerve cells (laboratory and animal research)Not enough evidence
Brain protection after stroke-like injury in rats (animal research)Very low certainty
Irritable bowel syndrome: a low-absorbable geraniol supplement (human trials)Low certainty
Cancer cells in the lab and in mice (laboratory and animal research, not treatment)Not enough evidence
Blood sugar, blood fats and organ damage in diabetic rats (animal research)Very low certainty
Inflammation: a psoriasis-like skin model in mice (animal and laboratory research)Very low certainty
Bacteria and yeast in the lab (laboratory and mouse research)Very low certainty
Mosquito and sand fly repellence (field and animal tests)Mixed findings

Lab markers tracked in the studies

Mechanical pain threshold in mice (von Frey test)CB1 receptor activation in cellsAnxiety-like behaviour in rats (open field, light-dark, social interaction)Brain damage area (infarct) after blood-flow loss in ratsGABA level in nerve cells and mouse brainIBS symptom severity score (IBS-SSS)Gut microbes (Faecalibacterium, Oscillospira)Tumour growth in mice with grafted or induced cancersBlood fats and liver and kidney function in diabetic ratsImmune messengers IL-2, TNF-alpha and IFN-gamma from human T cellsMRSA biofilm formation (lab)Mosquito and sand fly bites (repellency rate)

What is Geraniol good for?

The uses people ask about and how strong the evidence is for each. For pure geraniol, almost all of it is from animals or cells. The two human studies tested a gut-targeted supplement and are labelled that way. Cancer findings are laboratory work only.

Pain thresholds in mice (not shown in people)Very low certaintyIn mice with nerve, post-surgery or fibromyalgia-like pain, injected geraniol raised pain thresholds, the most strongly of four terpenes in one study. The work points to adenosine A2A receptors. The doses were 200 mg/kg injected, and there is no human trial. Cannabinoid-like activity in mice and cellsNot enough evidenceGeraniol produced cannabinoid-like behaviours in mice and activated the CB1 receptor in cells. This was not tested with THC or in people, so it does not show that geraniol changes how cannabis feels. Anxiety-like behaviour in ratsVery low certaintyOne rat study found less anxious behaviour after geraniol 10 and 30 mg/kg, similar to diazepam. No human data. Seizure-like activity in cells and miceNot enough evidenceOne study of nerve cells and mice found raised GABA and less injury. It is early animal work and not a treatment for epilepsy. Brain protection in rats after blood-flow lossVery low certaintyRats given geraniol before the injury had smaller damaged areas. One study, pre-treatment only. Irritable bowel syndrome: a low-absorbable geraniol supplementLow certaintyIn 56 adults with IBS, the symptom score after 4 weeks was 195 on the supplement and 265 on placebo, and 52.0% versus 16.7% responded. The study is small, and two authors founded the company behind the supplement. It does not apply to geraniol from food, flowers or oils. Cancer cells in the lab and in mice (laboratory research, not treatment)Not enough evidenceGeraniol slowed prostate, stomach and breast cancer cells in dishes and mice and added to the effect of chemotherapy drugs in mice. No human trial exists, and the dish concentrations are far above what the body reaches. Diabetic rats: blood fats, liver and kidneyVery low certaintyGeraniol improved blood fats and organ measures in diabetic rats at 100 to 200 mg/kg. No human data. Inflammation in a psoriasis-like mouse modelVery low certaintyGeraniol blocked the KV1.3 channel and eased psoriasis-like skin in mice. The effective concentration is high. MRSA biofilm and Candida in the labVery low certainty256 micrograms/mL geraniol cut MRSA biofilm formation by 86.13% in the lab. The same range of concentrations damaged chromosomes and fish embryos in another study. Mosquito and sand fly repellenceMixed findings5% geraniol candles repelled mosquitoes better than 5% citronella candles in one test (85.4% versus 29.0%); a 2% spray on ponies did not give a significant effect.

Benefits, one by one

Each card is a research question, not a promise. Tap a goal to filter. Open a card to see the studies, doses and limits.

Cannabinoid-like activity in mice and cells (laboratory research)

Not enough evidence

In mice, injected geraniol produced behaviours that scientists use as a marker of cannabinoid-like activity. In cells it switched on the CB1 receptor, the main receptor THC acts on. This is lab and animal work. It does not show that geraniol in cannabis changes how THC feels.

1 studiesPure geraniol injected into mice.

Studies, doses and limits

Results

Geraniol, alpha-humulene, linalool and beta-pinene produced cannabinoid-like behaviours in mice and their effects added to those of the lab cannabinoid drug WIN55,212.

Why this rating

One research group, mice and cells only, injected terpenes and a lab cannabinoid drug (not THC). The entourage idea has not been tested in people.

Form and dose studied

Pure geraniol injected into mice.

Who was studied

Mice (and cells).

Limits

Doses and routes do not match smoking, vaping or eating cannabis. Same lab group as the pain studies below. No human link.

Why researchers looked

Cannabis makes many terpenes besides THC and CBD. Researchers asked whether some terpenes act on the same brain systems or boost cannabinoids (the 'entourage effect' idea).

Traditional use

Geraniol is a rose-like molecule long used in perfume and flavour. It has no traditional use as a cannabis medicine.

Proposed mechanism Laboratory research

In cells all four terpenes tested activated the CB1 receptor, some also hit other targets. Some mouse behaviours were blocked by cannabinoid or adenosine receptor blockers, so the mechanism looks mixed.

A proposed mechanism does not show that the effect happens in people.

Not assessed in this study.

¹⁹

Pain thresholds in mice (animal research)

Very low certainty

In mice with nerve pain, post-surgery pain or fibromyalgia-like pain, injected geraniol raised the pain threshold, the most strongly of the terpenes tested in two of the studies. The effect seemed to go through adenosine A2A receptors. There is no human trial. This does not show that geraniol relieves pain in people.

3 studiesPure geraniol injected or given by mouth to animals at doses far abov…

Studies, doses and limits

Results

At 200 mg/kg injected into the abdomen, geraniol raised mechanical pain thresholds in post-operative and fibromyalgia-like pain models, strongest for geraniol, then linalool or alpha-humulene. In chemotherapy nerve-pain and inflammatory pain models the terpenes gave roughly the same relief as 10 mg/kg morphine. No reward effect was seen in a place-preference test. A low terpene dose with a low morphine dose worked better than either alone.

Effect sizes as reported

Numbers are in the full papers.

Why this rating

Animal research only, from one laboratory group, using injected doses (200 mg/kg) with no human equivalent. Reviewers have not graded it. Mouse pain results often fail to carry over to people.

Form and dose studied

Pure geraniol injected or given by mouth to animals at doses far above anything in food or fragrance.

Who was studied

Male and female mice.

Limits

All three papers come from the same group; high injected doses; hot-plate tests were unchanged, which argues against a general sedative effect but not against other side effects; no human data.

Why researchers looked

Opioid painkillers have serious problems, so researchers look for other pain pathways. Cannabis terpenes were tested as one source of ideas.

Proposed mechanism Animal research

A receptor blocker (istradefylline) and gene knockdown in the spinal cord removed the effect, and cell and computer work suggested the terpenes act as adenosine A2A receptor agonists.

A proposed mechanism does not show that the effect happens in people.

Safety in people at these exposures is unknown. See the Safety tab.

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Anxiety-like behaviour in rats (animal research)

Very low certainty

In rats made anxious by an electric foot shock, geraniol reduced anxious behaviour in a similar way to diazepam. This is one rat study. It does not show that geraniol calms people.

1 studiesPure geraniol given to rats at 10 or 30 mg/kg.

Studies, doses and limits

Results

Geraniol 10 and 30 mg/kg and diazepam reduced anxious behaviour in the open field, light-dark and social interaction tests and normalised EEG and brain chemistry.

Why this rating

A single rat study of a stress model. No replication was found and no human data exist.

Form and dose studied

Pure geraniol given to rats at 10 or 30 mg/kg.

Who was studied

Rats.

Limits

Short, single stress model; not an anxiety disorder; route and timing are not stated in the abstract.

Why researchers looked

Anxiety drugs often cause drowsiness or dependence, so natural molecules are tested in animal anxiety models first.

Traditional use

Geraniol-rich oils (rose, geranium) are used in aromatherapy, but no human trial of geraniol itself for anxiety was found.

Proposed mechanism Animal research

The authors link the effect to less oxidative stress, normal brain wave (EEG) patterns and restored hippocampal brain chemicals.

A proposed mechanism does not show that the effect happens in people.

Not assessed.

²⁶

Seizure-like activity in mice and nerve cells (laboratory and animal research)

Not enough evidence

In nerve cells and in mice made to have seizures with a chemical, geraniol reduced injury and raised the calming brain chemical GABA. This is early animal work. It is not a treatment for epilepsy.

1 studiesPure geraniol on cells and given to mice by mouth.

Studies, doses and limits

Results

In nerve cells (PC12) damaged by glutamate, geraniol at 100 to 200 micrograms/mL reduced injury and up to 400 micrograms/mL was not toxic. In mice with chemically induced seizures it raised GABA and lowered inflammatory markers, compared with the valproate group.

Why this rating

One study of cells and mice; the abstract does not give mouse dose units or seizure counts.

Form and dose studied

Pure geraniol on cells and given to mice by mouth.

Who was studied

PC12 nerve cells and mice.

Limits

Single study; chemical seizure model; comparison with valproate is in animals only.

Why researchers looked

Many seizure drugs act on GABA, so molecules that raise GABA are tested.

Proposed mechanism Animal research

Geraniol raised GABA and the enzymes that make it, and lowered inflammation and oxidative-stress markers in cells and mice.

A proposed mechanism does not show that the effect happens in people.

Not assessed.

⁴²

Brain protection after stroke-like injury in rats (animal research)

Very low certainty

In rats whose brain blood supply was briefly cut, rats given geraniol before the injury had smaller areas of damage and more surviving nerve cells. It is one rat study of pre-treatment. It does not show a stroke treatment.

1 studiesPure geraniol given to rats.

Studies, doses and limits

Results

Geraniol pre-treatment reversed rises in oxidative stress markers, reduced the infarct area and increased hippocampal CA1 nerve cell density, with better anxiety-related behaviour.

Why this rating

One rat study; geraniol was given before the injury, which cannot happen in a real stroke.

Form and dose studied

Pure geraniol given to rats.

Who was studied

Rats.

Limits

Pre-treatment; single model; dose not given in the abstract.

Why researchers looked

Researchers look for molecules that reduce the damage caused by lost and restored blood flow.

Proposed mechanism Animal research

The authors link the effect to less oxidative stress (lipid peroxidation, nitric oxide) and more antioxidant enzymes.

A proposed mechanism does not show that the effect happens in people.

Not assessed.

Irritable bowel syndrome: a low-absorbable geraniol supplement (human trials)

Low certainty

Two small Italian studies gave a special geraniol supplement, made to reach the lower gut, to people with irritable bowel syndrome. In the placebo-controlled trial, more people improved on geraniol (52.0% versus 16.7%). The studies are small, short, and two authors founded the company behind the supplement. This is not geraniol from food, flowers or essential oil.

2 studiesA food supplement formulated to release geraniol in the lower gut (pr…

Studies, doses and limits

What the trials found

A double-blind, placebo-controlled trial in 56 adults with IBS (Rome III criteria) gave a low-absorbable geraniol supplement once a day for four weeks. The IBS symptom score was 195 with geraniol versus 265 with placebo (p = 0.001). The responder rate (a fall of 50 points or more) was 52.0% versus 16.7% (p = 0.009), mainly in the mixed IBS subtype. An earlier before-and-after pilot (no placebo group, up to 8 mg/kg/day for 4 weeks in a delayed-release form) also found lower symptom scores and more of the gut microbes Collinsella and Faecalibacterium.

Results

IBS-SSS 195 versus 265 (p = 0.001); responders 52.0% versus 16.7% (p = 0.009).

Effect sizes as reported

Not reported in the abstracts.

Why this rating

One small randomised trial (56 people, 4 weeks) plus an uncontrolled pilot. No review gave a GRADE rating. Two authors founded the start-up behind the supplement. Not repeated by an independent group that we found.

Form and dose studied

A food supplement formulated to release geraniol in the lower gut (product details not in the abstracts). Do not assume it matches any other form of geraniol.

Who was studied

Adults with IBS (Rome III) in Italy.

Limits

Small, short, industry-linked; dose not given in the abstract of the trial; the pilot had no control group and was registered after it ran.

Why researchers looked

Geraniol has anti-inflammatory and antimicrobial effects in the lab, and researchers wanted to see if it could calm the gut and change gut microbes.

Proposed mechanism Controlled trial

The authors suggest it changes the balance of gut microbes (less Oscillospira, a trend to more Faecalibacterium). Blood inflammation markers did not differ from placebo in the trial.

A proposed mechanism does not show that the effect happens in people.

The abstracts do not report side effects. Geraniol is a known skin allergen when it has reacted with air; this is not a bowel effect.

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Cancer cells in the lab and in mice (laboratory and animal research, not treatment)

Not enough evidence

In dishes and in mice, geraniol slowed the growth of prostate, stomach and breast cancer cells and made some die by apoptosis (planned cell death), and in mice it added to the effect of the chemotherapy drugs docetaxel and 5-fluorouracil. This is lab work. It does not mean geraniol treats or prevents cancer, and no human trial exists.

8 studiesPure geraniol on cells or in animals, sometimes with chemotherapy dru…

Studies, doses and limits

Results

PC-3 prostate cancer cells and grafted mice: cell cycle arrest, apoptosis and, with low doses of docetaxel, less tumour growth (2011). Gastric cancer cells and xenografts: lower viability, G0/G1 arrest, more apoptosis, less beta-catenin (2026). Mice with breast carcinoma: smaller tumours; with 5-fluorouracil more than 82% tumour inhibition (2023).

Effect sizes as reported

Numbers are in the full papers.

Why this rating

Cell lines and mouse grafts only; concentrations used in dishes are far above what the body reaches from food or fragrance (blood levels in mice after a 200 mg/kg oral dose were about 0.05 micrograms/mL). Reviews say the work is promising but preclinical.

Form and dose studied

Pure geraniol on cells or in animals, sometimes with chemotherapy drugs. No cannabis product.

Who was studied

Cancer cell lines and mice.

Limits

No human trial; dish concentrations are unrealistic; one study (human blood cells) found geraniol and related oils harmful to cells at higher concentrations. Do not use geraniol products in place of cancer treatment.

Why researchers looked

Researchers screen plant molecules for cell-killing effects, and geraniol has been widely explored in cancer cell lines.

Proposed mechanism Laboratory research

In the studies read geraniol arrested the cell cycle, raised cell-death proteins (Bax) and affected Wnt/beta-catenin and miR-21/PTEN signalling.

A proposed mechanism does not show that the effect happens in people.

A study of human blood cells found DNA damage with citral and essential oils at higher concentrations. See the Safety tab.

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Blood sugar, blood fats and organ damage in diabetic rats (animal research)

Very low certainty

In rats made diabetic by diet and a chemical, geraniol improved blood fats and liver and kidney measures. Reviews call the findings promising for metabolic disease. There are no human trials of geraniol for diabetes.

2 studiesPure geraniol given to rats.

Studies, doses and limits

Results

At 100 and 200 mg/kg for 6 weeks in rats given a high-fat diet and streptozotocin, geraniol improved lipid profile, liver and kidney function, antioxidant enzymes and cell-death markers.

Why this rating

One rat study at high doses, plus a narrative review of preclinical work. No human data.

Form and dose studied

Pure geraniol given to rats.

Who was studied

Rats.

Limits

Doses of 100 to 200 mg/kg; single model; no human data.

Why researchers looked

Geraniol has antioxidant and anti-inflammatory effects, so researchers tested it in diabetic animals.

Proposed mechanism Animal research

Computer docking suggested geraniol can bind alpha-amylase and alpha-glucosidase; the authors also report lower cell-death markers in kidney and liver.

A proposed mechanism does not show that the effect happens in people.

Not assessed.

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Inflammation: a psoriasis-like skin model in mice (animal and laboratory research)

Very low certainty

Geraniol blocked an ion channel (KV1.3) on immune cells, lowered immune messenger release from human T cells in the lab, and eased a psoriasis-like skin condition in mice. This is early lab and mouse work. It is not a treatment for psoriasis.

1 studiesPure geraniol on cells and given to mice.

Studies, doses and limits

Results

In imiquimod-treated mice geraniol lowered the psoriasis area and severity score, improved skin histology and reduced spleen enlargement.

Effect sizes as reported

IC50 about 490 micromolar for the KV1.3 channel.

Why this rating

One study of cells and mice; the effective concentration is high.

Form and dose studied

Pure geraniol on cells and given to mice.

Who was studied

Human T cells in the lab; mice.

Limits

Single study; a mouse skin model does not predict human psoriasis. Geraniol applied to skin can itself cause allergy in some people.

Why researchers looked

KV1.3 channel blockers are being explored for autoimmune and chronic inflammatory disease.

Proposed mechanism Laboratory research

Geraniol blocked KV1.3 currents with an IC50 of about 490 micromolar, a high concentration, and lowered IL-2, TNF-alpha and IFN-gamma release from activated human T cells.

A proposed mechanism does not show that the effect happens in people.

Geraniol is a known skin allergen once it has reacted with air (see the Safety tab).

⁴¹

Bacteria and yeast in the lab (laboratory and mouse research)

Very low certainty

In the lab geraniol held back the biofilm of MRSA, a drug-resistant staph bacterium, and slowed Candida yeasts. With the antibiotic vancomycin it reduced biofilm on an implant in mice. This is lab work, not an infection treatment, and geraniol was also toxic to cells and fish embryos at the highest concentrations tested.

2 studiesPure geraniol in the lab; not a mouthwash, spray or oil recommendatio…

Studies, doses and limits

Results

256 micrograms/mL geraniol cut MRSA biofilm formation by 86.13% and removed 49.87% of mature biofilm; with vancomycin it reduced biofilm on an implant in mice. Geraniol also inhibited five Candida species, more strongly than linalool, but at 800 micrograms/mL it raised chromosome damage, and the LC50 for zebrafish embryos was 31.3 micrograms/mL.

Effect sizes as reported

MRSA biofilm formation down 86.13% at 256 micrograms/mL (lab).

Why this rating

Laboratory concentrations and a mouse implant model; no human use data.

Form and dose studied

Pure geraniol in the lab; not a mouthwash, spray or oil recommendation.

Who was studied

Bacteria, yeast, human cells, zebrafish embryos and mice.

Limits

Concentrations near the toxic range; no human infection trial.

Why researchers looked

Drug-resistant infections are a big problem, so plant molecules are tested against them.

Proposed mechanism Laboratory research

Geraniol lowered the build-up of the bacterial biofilm and virulence factors; the abstract does not describe yeast mechanisms.

A proposed mechanism does not show that the effect happens in people.

Genotoxic and embryotoxic effects were seen at the highest concentrations in one study.

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Mosquito and sand fly repellence (field and animal tests)

Mixed findings

A candle test in a high-biting setting found 5% geraniol candles repelled mosquitoes better than 5% citronella candles (85.4% versus 29.0%). A spray test with a 2% water solution on ponies did not show a significant effect. Results depend a lot on the product and test.

2 studiesCandles at 5% and a 2% aqueous mist on ponies in the studies.

Studies, doses and limits

What the trials found

A human landing-assay candle test found repellency against mosquitoes of 85.4% for geraniol, 71.1% for linalool and 29.0% for citronella candles, and against sand flies 79.7%, 55.2% and 24.7%. A 2010 trial on ponies with 2% geraniol mist found no significant difference from untreated animals (P = 0.081).

Results

Candle repellency against mosquitoes: 85.4% (geraniol) versus 29.0% (citronella).

Why this rating

Two small, differing tests: one favourable candle test, one non-significant pony test. No long-term or skin-spray trial on people was read.

Form and dose studied

Candles at 5% and a 2% aqueous mist on ponies in the studies.

Who was studied

Human volunteers (candles); ponies (spray).

Limits

The abstracts do not give numbers of volunteers; candle results do not apply to skin products. Geraniol may cause allergy in humans and animals (the pony paper itself says so).

Why researchers looked

Geraniol is used in some natural insect repellents.

Traditional use

Citronella and geranium oils are traditional mosquito deterrents.

Proposed mechanism Other

Not described in the abstracts.

A proposed mechanism does not show that the effect happens in people.

Geraniol is a known skin allergen once it has reacted with air (see the Safety tab).

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Connections to the rest of health

How Geraniol connects to the rest of our health knowledge graph. Every link says what kind of connection it is. A safety link (for example to the liver) is a warning, not a benefit. A study that merely mentions a topic never creates a benefit link.

Explore every connection: goals, body systems, organs, symptoms, genes

Kind of connection Connected to Search

B. Body systems

Connected to	Kind of connection	Evidence status	Context	Studies
Digestive system		Low certainty	One 56-person trial and one pilot in irritable bowel syndrome. Preparation or compound: Low-absorbable geraniol supplement	^{29 30}
Nervous system		Very low certainty	Pain, anxiety-like behaviour, seizures and brain protection in animals only. Preparation or compound: Pure geraniol (mice, rats, cells)	^{32 31 26}
Nervous System	Biological association	Not enough evidence	Studied for: Cannabinoid-like activity in mice and cells (laboratory research) Studied for: Pain thresholds in mice (animal research)	^{19 32 31 26 42 3}
Digestive System	Biological association	Low certainty	Studied for: Irritable bowel syndrome: a low-absorbable geraniol supplement (human trials)	^{29 30}
Immune System	Biological association	Not enough evidence	Studied for: Cancer cells in the lab and in mice (laboratory and animal research, not treatment) Studied for: Inflammation: a psoriasis-like skin model in mice (animal and laboratory research)	^{18 43 6 33 25 21 23 36 41 7 35}
Endocrine System	Biological association	Very low certainty	Studied for: Blood sugar, blood fats and organ damage in diabetic rats (animal research)	^{5 34}

C. Body parts and organs

Connected to	Kind of connection	Evidence status	Context	Studies
Skin	Adverse effect or risk	Moderate certainty	About 3% to 8% of patch-tested dermatitis patients reacted to oxidised geraniol at 6% to 11%; pure geraniol detected far fewer. Preparation or compound: Oxidised geraniol (air-exposed) in products and oils	^{13 11 2}

E. Health conditions

Connected to	Kind of connection	Evidence status	Context	Studies
Cancer (laboratory research only)		Not enough evidence	Cell and mouse studies; no human trial; no treatment claim. Preparation or compound: Pure geraniol in cells and mice	^{18 43 6}

I. Biomarkers

Connected to	Kind of connection	Evidence status	Context	Studies
Mechanical pain threshold in mice (von Frey test)	Biological association	Very low certainty	Measured in trials: raised. A lab change is not the same as a health benefit.	^{32 31}
CB1 receptor activation in cells	Biological association	Not enough evidence	Measured in trials: raised. A lab change is not the same as a health benefit.	¹⁹
Anxiety-like behaviour in rats (open field, light-dark, social interaction)	Biological association	Very low certainty	Measured in trials: lowered. A lab change is not the same as a health benefit.	²⁶
Brain damage area (infarct) after blood-flow loss in rats	Biological association	Very low certainty	Measured in trials: lowered. A lab change is not the same as a health benefit.	³
GABA level in nerve cells and mouse brain	Biological association	Not enough evidence	Measured in trials: raised. A lab change is not the same as a health benefit.	⁴²
IBS symptom severity score (IBS-SSS)	Biological association	Low certainty	Measured in trials: lowered. A lab change is not the same as a health benefit.	^{29 30}
Gut microbes (Faecalibacterium, Oscillospira)	Biological association	Low certainty	Measured in trials: mixed. A lab change is not the same as a health benefit.	^{29 30}
Tumour growth in mice with grafted or induced cancers	Biological association	Not enough evidence	Measured in trials: lowered. A lab change is not the same as a health benefit.	^{6 18 43 36}
Blood fats and liver and kidney function in diabetic rats	Biological association	Very low certainty	Measured in trials: mixed. A lab change is not the same as a health benefit.	⁵
Immune messengers IL-2, TNF-alpha and IFN-gamma from human T cells	Biological association	Very low certainty	Measured in trials: lowered. A lab change is not the same as a health benefit.	⁴¹
MRSA biofilm formation (lab)	Biological association	Very low certainty	Measured in trials: lowered. A lab change is not the same as a health benefit.	^{7 35}
Mosquito and sand fly bites (repellency rate)	Biological association	Mixed findings	Measured in trials: mixed. A lab change is not the same as a health benefit.	^{24 28}

L. Active compounds

Connected to	Kind of connection	Evidence status	Context	Studies
Geraniol	Biological association	Mixed findings	Studied in animals and cells for pain, anxiety-like behaviour, seizures, cancer cells, diabetes, inflammation and microbes; the only human trials are two small IBS studies of a supplement. Preparation or compound: Rose petals (rose oil and water), geranium leaves, Cymbopogon grasses (citronella, lemongrass, palmarosa)	^{40 17 4 29 19}
Geranial and neral (citral)	Biological association	Moderate certainty	Formed when geraniol oxidises or is changed by skin enzymes; the main allergens behind geraniol allergy. Citral allergy was 2.9% in one patch-test series. Preparation or compound: Lemongrass and other Cymbopogon oils	^{8 9 14}
Geranic acid and Hildebrandt acid (metabolites)	Biological association	Low certainty	The main geraniol metabolites in human urine: Hildebrandt acid 34.4% and geranic acid 12.7% of the dose. The CID given is for geranic acid.	^{16 23}
Citronellol	Biological association	Not enough evidence	Often travels with geraniol in rose and geranium oils; not covered further here. Preparation or compound: Rose and geranium oils	^{40 17}
Nerol	Biological association	Not enough evidence	The cis isomer of geraniol; reviewed together with geraniol for anticancer effects in cells. Preparation or compound: Rose oils	^{40 33}
Linalool	Biological association	Mixed findings	A cannabis terpene tested alongside geraniol in the same mouse studies; the more studied relative. See the linalool page. Preparation or compound: Lavender, coriander, cannabis	^{19 32}

Each connection is stored with the ingredient, the connected record, the kind of connection, the evidence status, the supporting studies, the preparation or compound involved, and a review date (last reviewed October 25, 2026).

Evidence at a glance: what changed in 12 lab markers

Tap a number to show only those markers. Counts are markers, not people.

Other633

The evidence

The research centre for Geraniol. Every record here was checked against PubMed or the publisher's page; we never list a study we have not verified.

Evidence by outcome

Cannabinoid-like activity in mice and cells (laboratory research) 1 study Not enough evidence Pain thresholds in mice (animal research) 3 studies Very low certainty Anxiety-like behaviour in rats (animal research) 1 study Very low certainty Seizure-like activity in mice and nerve cells (laboratory and animal research) 1 study Not enough evidence Brain protection after stroke-like injury in rats (animal research) 1 study Very low certainty Irritable bowel syndrome: a low-absorbable geraniol supplement (human trials) 2 studies · 56 people in trials Low certainty Cancer cells in the lab and in mice (laboratory and animal research, not treatment) 8 studies Not enough evidence Blood sugar, blood fats and organ damage in diabetic rats (animal research) 2 studies Very low certainty Inflammation: a psoriasis-like skin model in mice (animal and laboratory research) 1 study Very low certainty Bacteria and yeast in the lab (laboratory and mouse research) 2 studies Very low certainty Mosquito and sand fly repellence (field and animal tests) 2 studies Mixed findings

Bars show how many studies we found for each outcome, not how well it works. People are added up across trials only (reviews are not added, to avoid double counting).

How we rate evidence

High certainty

Several well-run trials or reviews agree; further research is unlikely to change the picture much.

Moderate certainty

Good trials point the same way, but some doubt remains.

Low certainty

Small, short or inconsistent trials. The finding could change with better research.

Very low certainty

Very little or very weak human data. Treat as a possibility only.

Mixed findings

Trials or reviews disagree with each other.

Not enough evidence

Not enough human research to say either way.

Evidence against

Good research found no benefit, or found harm.

We take the reviewers' own risk-of-bias and GRADE statements where they exist, and otherwise judge from study size, design, consistency, directness and whether a product matches what is sold. Many publications do not make evidence high. Method note: We searched PubMed and read the abstracts of 41 papers, read the FDA flavouring list through the Electronic Code of Federal Regulations and PubChem for identity. Only abstracts were read for papers. Certainty ratings are the compiler's own reading; no review we read gave a GRADE rating. EUR-Lex (EU rules), EFSA, LiverTox and LactMed were not read. The lab numbers are from a published table, not our own testing.

Study library: every study we checked 43

Design Research type Year from Search

Study	Design	People	Product, dose, length	Result
Api 2022 RIFM fragrance ingredient safety assessment, geraniol, CAS registry number 106-24-1 Food Chem Toxicol · PMID 35940332 · DOI	Authoritative guidance n/a	Safety assessment by the fragrance industry's research institute (RIFM) expert panel	Geraniol (CAS 106-24-1) as a fragrance ingredient	The panel reports that geraniol is not genotoxic, has a margin of exposure above 100 for repeated-dose and reproductive toxicity, a No Expected Sensitization Induction Level of 11,000 micrograms per square centimetre for skin sensitisation, is not expected to be phototoxic, and that exposure is below the respiratory threshold of 1.4 mg a day. It concludes the existing information supports use as described. Industry panel finds current fragrance use acceptable Methods, limits and funding Outcomes: Genotoxicity, repeated-dose and reproductive toxicity, skin sensitisation, phototoxicity, respiratory and environmental safety Limitations: Written by the fragrance industry's own research institute (RIFM), whose staff are authors; the panel receives a small honorarium. Not an independent regulator. Funding and conflicts: Research Institute for Fragrance Materials (industry); authors declare no competing interests Read: abstract
Bruze 2024 Contact allergy to oxidised geraniol may be over-represented in individuals with photocontact allergy to ketoprofen Contact Dermatitis · PMID 37840237 · DOI	Observational	Routinely patch-tested dermatitis patients in Sweden, compared with four patients with photocontact allergy to ketoprofen	Oxidised geraniol 11% and 6%, geraniol 6%, geranial, neral and citral (patch tests) see intervention (patch test)	Allergic reactions were seen to oxidised geraniol 11% in 39 patients (5.8%), oxidised geraniol 6% in 12 (1.8%), geraniol 6% in 2 (0.3%), geranial in 18 (2.7%), neral in 7 (1.0%) and citral in 15 (2.2%). The four patients with ketoprofen photoallergy had more reactions to oxidised geraniol 11% than expected (p = 0.020). Allergy to oxidised geraniol, geranial and citral is common in routinely tested dermatitis patients Methods, limits and funding Outcomes: Allergic patch-test reactions Limitations: The abstract gives percentages rather than the total (about 670 patients, worked out from 39 cases = 5.8%). Only four ketoprofen patients. Funding and conflicts: Not stated in the abstract Read: abstract
Buch 2023 Geraniol protects hippocampal CA1 neurons and improves functional outcomes in global model of stroke in rats Chem Biol Drug Des · PMID 37118873 · DOI	Animal experiment rat	Rats with brain blood-flow loss (global ischaemia)	Geraniol pre-treatment	Geraniol reversed rises in oxidative stress markers, reduced the infarct area and protected nerve cells in the hippocampus, with better anxiety-related behaviour. Brain protection in a rat stroke model Methods, limits and funding Outcomes: Oxidative stress markers, infarct size, behaviour Limitations: Given before injury; rat model; no dose in the abstract. Funding and conflicts: Not stated in the abstract Read: abstract
Dangol 2023 Essential Oil Composition Analysis of Cymbopogon Species from Eastern Nepal by GC-MS and Chiral GC-MS, and Antimicrobial Activity of Some Major Compounds Molecules · PMID 36677603 · DOI	Lab analysis plant	Cymbopogon oils from Eastern Nepal: citronella (C. winterianus), lemongrass (C. citratus) and palmarosa (C. martini)	Essential oils from roots and leaves	The abstract reports geraniol as 37.1% of one citronella oil fraction and 76.6% (leaves) and 87.9% (root) in lemongrass oil, with geranyl acetate also present, while palmarosa leaf oil was mostly neral (36.1%) and geranial (53.1%). The authors say citral (neral and geranial) is normally the main compound in these plants, so these values are not typical of every oil. Geraniol ranged from very high to absent depending on species, plant part and sample Methods, limits and funding Outcomes: Composition by GC-MS Limitations: The abstract's wording about which sample belongs to which species is hard to follow; treat the values as one Nepal sample set. Funding and conflicts: Not stated in the abstract Read: abstract
El Azab 2022 Geraniol ameliorates the progression of high fat-diet/streptozotocin-induced type 2 diabetes mellitus in rats via regulation of caspase-3, Bcl-2, and Bax expression J Food Biochem · PMID 35312192 · DOI	Animal experiment rat	Rats with type 2 diabetes induced by high-fat diet and streptozotocin	Geraniol 100 and 200 mg/kg 6 weeks	Geraniol improved blood fats and liver and kidney function and antioxidant enzymes, and lowered cell-death markers. Computer docking suggested it can bind the enzymes alpha-amylase and alpha-glucosidase. Better kidney and liver measures in diabetic rats Methods, limits and funding Outcomes: Blood fats, liver and kidney function, oxidative stress Limitations: Rats only; high doses. Funding and conflicts: Not stated in the abstract Read: abstract
El-Ganainy 2023 Geraniol suppresses tumour growth and enhances chemosensitivity of 5-fluorouracil on breast carcinoma in mice: involvement of miR-21/PTEN signalling J Pharm Pharmacol · PMID 37379815 · DOI	Animal experiment mouse	Mice with induced breast carcinoma	Geraniol, alone and with 5-fluorouracil	Geraniol suppressed tumour growth with lower miR-21 and higher PTEN. Geraniol plus 5-fluorouracil gave more than 82% inhibition of tumour rate, more than either alone. Smaller tumours in mice with induced breast cancer Methods, limits and funding Outcomes: Tumour growth and signalling markers Limitations: Mouse model only; no human data. Funding and conflicts: Not stated in the abstract Read: abstract
Gu 2022 Geraniol inhibits biofilm formation of methicillin-resistant Staphylococcus aureus and increase the therapeutic effect of vancomycin in vivo Front Microbiol · PMID 36147840 · DOI	Animal experiment bacteria and mouse	Methicillin-resistant Staphylococcus aureus (MRSA) biofilms in the lab and a mouse implant infection	Geraniol, alone and with vancomycin 256 micrograms/mL in the lab	Geraniol at 256 micrograms/mL inhibited MRSA biofilm formation by 86.13% and removed mature biofilm by 49.87%. With vancomycin it reduced biofilm on an implant in mice. Reduced MRSA biofilm in the lab and in mice Methods, limits and funding Outcomes: Biofilm formation and removal Limitations: Lab concentration; mouse implant model; no human data. Funding and conflicts: Not stated in the abstract Read: abstract
Hagvall 2007 Fragrance compound geraniol forms contact allergens on air exposure. Identification and quantification of oxidation products and effect on skin sensitization Chem Res Toxicol · PMID 17428070 · DOI	Lab analysis mouse	Chemistry in the lab plus the mouse local lymph node assay (a skin-allergy test)	Pure geraniol, air-exposed geraniol and its oxidation products	Geraniol exposed to air at room temperature formed hydrogen peroxide, the aldehydes geranial and neral, and a small amount of a hydroperoxide. The air-exposed samples were moderate skin sensitisers, quite different from pure geraniol. The authors believe the hydroperoxide, together with geranial and neral, causes most of the allergy. Air-exposed geraniol was a moderate sensitiser in mice; pure geraniol was far weaker Methods, limits and funding Outcomes: Which products form when geraniol meets air, and how strongly each one sensitises mouse skin Limitations: Mouse and chemistry work; the abstract gives no numbers for potency. Funding and conflicts: Not stated in the abstract Read: abstract
Hagvall 2008 Cytochrome P450-mediated activation of the fragrance compound geraniol forms potent contact allergens Toxicol Appl Pharmacol · PMID 18824010 · DOI	Laboratory research lab (human skin enzymes) and mouse	Lab incubations with a mix of skin enzymes (a skin-like CYP cocktail), then mouse skin-allergy tests	Geraniol and its breakdown products	Skin-like enzyme mixes turned geraniol mainly into geranial (plus neral and epoxide forms). In mouse tests geranial, neral and 6,7-epoxygeraniol were moderate sensitisers and 6,7-epoxygeranial a strong one. The authors say geraniol is activated both by air and by the skin's own enzymes (probably CYP1A1 and CYP3A5). Geraniol can become allergenic in two ways: by air and by skin metabolism Methods, limits and funding Outcomes: Whether skin enzymes turn geraniol into allergens Limitations: Lab and mouse work; the abstract does not give potency numbers. Funding and conflicts: Not stated in the abstract Read: abstract
Hagvall 2012 Contact allergy to air-exposed geraniol: clinical observations and report of 14 cases Contact Dermatitis · PMID 22681463 · DOI	Observational	2227 Consecutive dermatitis patients patch tested in a Swedish clinic	Pure geraniol and air-exposed (oxidised) geraniol, each at 2.0% in petrolatum 2.0% in petrolatum (patch test)	Pure geraniol gave positive patch-test reactions in 0.13% of patients and oxidised geraniol in 0.55%. Eight of 11 patients with a positive reaction to oxidised geraniol also reacted to citral or its parts. Fourteen cases were described and 11 of them were judged relevant to the patient's rash. 0.13% positive to pure geraniol versus 0.55% to oxidised geraniol Methods, limits and funding Outcomes: Positive patch-test reactions Limitations: Patients already referred for skin problems, so the rate in the general public is lower. One clinic. Funding and conflicts: Not stated in the abstract Read: abstract
Hagvall 2013 Finding the optimal patch test material and test concentration to detect contact allergy to geraniol Contact Dermatitis · PMID 23510343 · DOI	Observational	655 Patients patch tested in one Swedish clinic	Pure and oxidised geraniol at 4.0%, 6.0% and 11.0% in petrolatum 4%, 6%, 11% in petrolatum (patch test)	Pure geraniol detected positive reactions in 0.15% to 1.1% of patients, and oxidised geraniol in 0.92% to 4.6%, rising with test strength. Neither gave significant irritant reactions (tested in 27 patients). Some patients reacted only to pure geraniol, which points to skin metabolism as a second route. Oxidised geraniol finds more allergic patients than pure geraniol, but neither finds all Methods, limits and funding Outcomes: Positive reactions and irritation at different test strengths Limitations: Clinic patients; test strengths are far higher than in products. Funding and conflicts: Not stated in the abstract Read: abstract
Hagvall 2014 Cross-reactivity between citral and geraniol - can it be attributed to oxidized geraniol? Contact Dermatitis · PMID 25209002 · DOI	Observational	655 Patients patch tested in one Swedish clinic	Geranial, neral and citral 3.5%; pure geraniol 6% and 11%; oxidised geraniol 6% in petrolatum see intervention (patch test)	Among patients who reacted to citral, 26% reacted to oxidised geraniol and 10.5% to pure geraniol. Citral or its parts gave positive reactions in 25% of patients who reacted to pure geraniol. The authors conclude there is little cross-reaction between pure geraniol and citral, but reactions to citral and oxidised geraniol often go together, because of geranial. Geranial, formed when geraniol oxidises, is the main shared allergen Methods, limits and funding Outcomes: Cross-reactions between citral and geraniol Limitations: Clinic patients, one centre. Funding and conflicts: Not stated in the abstract Read: abstract
Hagvall 2018 Contact allergy to oxidized geraniol among Swedish dermatitis patients-A multicentre study by the Swedish Contact Dermatitis Research Group Contact Dermatitis · PMID 29926925 · DOI	Observational	1476 Consecutive dermatitis patients referred for patch testing at several Swedish clinics	Pure geraniol 6%, oxidised geraniol 6% and 11% in petrolatum 6% and 11% in petrolatum (patch test)	Pure geraniol 6%, oxidised geraniol 6% and oxidised geraniol 11% gave 1%, 3% and 8% positive reactions, and 0.7%, 3% and 5% doubtful reactions. Most patients who reacted did so only to oxidised geraniol. The authors say it should be explored whether oxidised geraniol belongs in the baseline patch-test series. Up to 8% of patch-tested dermatitis patients reacted to oxidised geraniol at the highest test strength Methods, limits and funding Outcomes: Positive and doubtful patch-test reactions Limitations: Patients already seen for suspected allergy; the high test strength may include some irritation; not the general public. Funding and conflicts: Not stated in the abstract Read: abstract
Hagvall 2020 Contact allergy to citral and its constituents geranial and neral, coupled with reactions to the prehapten and prohapten geraniol Contact Dermatitis · PMID 31566752 · DOI	Observational	1476 Consecutive dermatitis patients with suspected contact allergy at several Swedish clinics	Geranial, neral, citral 3.5%; geraniol 6%; oxidised geraniol 11% in petrolatum see intervention (patch test)	Positive reactions were 2.9% for citral, 3.4% for geranial and 1.9% for neral. Among patients who reacted to citral or its parts, 61% reacted to oxidised geraniol. The authors conclude that patch testing with pure geraniol is of little value, and that oxidised geraniol or citral find allergies the standard series misses. Citral-family allergy overlaps strongly with oxidised geraniol allergy Methods, limits and funding Outcomes: Positive patch-test reactions to citral, its parts and oxidised geraniol Limitations: Clinic patients, not the general public. Funding and conflicts: Not stated in the abstract Read: abstract
Hallahan 1995 Cytochrome P-450 in plant/insect interactions: geraniol 10-hydroxylase and the biosynthesis of iridoid monoterpenoids Drug Metabol Drug Interact · PMID 8820862 · DOI	Review plant	Review plus plant enzyme experiments (Catharanthus roseus and Nepeta racemosa)	Plant cytochrome P450 enzymes acting on geraniol, nerol and citronellol	A key step in making the iridoid class of plant terpenes is the geraniol/nerol 10-hydroxylase, a P450 enzyme. The enzymes from the two plants tested could hydroxylate geraniol, nerol and citronellol, so they do not fix the starting molecule. Geraniol is a starting molecule for plant iridoid compounds Methods, limits and funding Outcomes: How plants use geraniol to make iridoid compounds Limitations: Old (1995) plant biochemistry; says nothing about cannabis. Funding and conflicts: Not stated in the abstract Read: abstract
Jäger 2023 Human Metabolism and Urinary Elimination Kinetics of the Fragrance Geraniol after Oral Dosage Chem Res Toxicol · PMID 37921539 · DOI	Pharmacokinetic	3 Three volunteers	Single oral geraniol 25 mg or 250 mg (research doses) Single dose, urine collected for 72 hours	Peak urine levels of the metabolites came 1 to 5 hours after dosing, with elimination half-lives of about 2 to 4 hours. The main metabolite was Hildebrandt acid (34.4 +/- 5.6% of the dose), then geranic acid (12.7 +/- 5.6%). The four metabolites together were 41.7% to 55.5% of the dose. From 41 urine samples of adults without work exposure, the authors estimated an average daily geraniol intake of 1.43 mg. Geraniol is quickly broken down and passed in urine Methods, limits and funding Outcomes: Urinary metabolites over 72 hours Limitations: Only three people. Funding and conflicts: Not stated in the abstract Read: abstract
Kačániová 2023 An In-Depth Study on the Chemical Composition and Biological Effects of Pelargonium graveolens Essential Oil Foods · PMID 38201061 · DOI	Lab analysis plant	One Pelargonium graveolens (rose-scented geranium) essential oil	Geranium essential oil Leaves (not stated in the abstract)	The main compounds were beta-citronellol (29.7%) and geraniol (14.6%), out of 99.2% of volatiles identified. Geraniol was 14.6% of one geranium oil Methods, limits and funding Outcomes: Composition by GC-MS Limitations: One oil sample. Funding and conflicts: Not stated in the abstract Read: abstract
Kim 2011 Geraniol inhibits prostate cancer growth by targeting cell cycle and apoptosis pathways Biochem Biophys Res Commun · PMID 21371438 · DOI	Animal experiment human cells and mouse	Human PC-3 prostate cancer cells in the lab and in mice carrying grafted tumours	Geraniol, alone and with docetaxel	Geraniol caused cell cycle arrest and apoptosis (programmed cell death) in the cancer cells and in grafted mice, and low doses of geraniol with docetaxel suppressed tumour growth more than usual in cells and mice. Laboratory and mouse effect on one prostate cancer cell line Methods, limits and funding Outcomes: Cell cycle, cell death and tumour growth Limitations: One cell line and mouse grafts; not a human trial; no treatment claim can be made. Funding and conflicts: Not stated in the abstract Read: abstract
LaVigne 2021 Cannabis sativa terpenes are cannabimimetic and selectively enhance cannabinoid activity Sci Rep · PMID 33859287 · DOI	Animal experiment mouse and lab cells	Mice (cannabinoid 'tetrad' behaviour tests) and cells in the lab	Geraniol, alpha-humulene, linalool and beta-pinene, alone and with the cannabinoid drug WIN55,212	Geraniol, alpha-humulene, linalool and beta-pinene produced cannabinoid-like behaviours in mice. Some could be blocked by cannabinoid or adenosine receptor blockers. The effects added to those of WIN55,212. In cells, all the terpenes activated the CB1 receptor, some also other targets. The authors say the work supports the 'entourage effect' idea. Cannabinoid-like activity in mice and cells Methods, limits and funding Outcomes: Cannabinoid-like behaviours in mice and receptor activation in cells Limitations: Mouse and cell work with injected terpenes; WIN55,212 is a lab cannabinoid drug, not THC; the entourage idea remains debated and was not tested in people. Funding and conflicts: Not stated in the abstract Read: abstract
Lee 2025 Probabilistic risk assessment of emerging EU-regulated fragrance allergens in household and personal care products Environ Int · PMID 40398361 · DOI	Lab analysis n/a	267 267 household and personal care products in South Korea	56 fragrance allergens	The authors state that 30 of the 56 allergens were newly designated as mandatory labelling substances under Commission Regulation (EU) 2023/1545 of 26 July 2023, which amends Regulation (EC) No 1223/2009. Limonene, linalool and alpha-terpineol were the most often found. The abstract does not name geraniol. Confirms the existence of the 2023 EU fragrance-allergen labelling regulation Methods, limits and funding Outcomes: Allergen quantities and risk Limitations: Abstract does not mention geraniol; used only to confirm the regulation exists. Funding and conflicts: Not stated in the abstract Read: abstract
Lei 2019 Pharmacological Properties of Geraniol - A Review Planta Med · PMID 30308694 · DOI	Review mixed	Review of laboratory, animal and few human reports from the last 6 years	Geraniol	The review summarises anti-tumour, anti-inflammatory, antioxidant and antimicrobial effects and liver, heart and brain protection, and concludes geraniol is a promising drug candidate. It lists these as pharmacological findings, not clinical proof. Narrative review: promising lab and animal activity Methods, limits and funding Outcomes: Pharmacological properties Limitations: Narrative review without a stated quality rating; mostly lab and animal studies. Funding and conflicts: Authors declare no conflict of interest Read: abstract
Moein 2014 Chemical composition analysis of rose water samples from Iran Pharm Biol · PMID 24863280 · DOI	Lab analysis plant	10 Ten rose water samples bought in Shiraz, Iran	Rose water (hydrosol)	Phenethyl alcohol, geraniol and beta-citronellol were the main constituents of most samples. Pelargonium and Dianthus oils and synthetic essences had been added to some, and dibutyl phthalate was found in most. Geraniol is a main component of most rose waters sold, some adulterated Methods, limits and funding Outcomes: Composition and quality Limitations: Ten local samples. Funding and conflicts: Not stated in the abstract Read: abstract
Moriki 2025 Pharmacokinetics of Geraniol and Its Metabolites in Mice After Oral Administration Food Sci Nutr · PMID 39803254 · DOI	Animal experiment mouse	C57BL/6J mice	Geraniol by mouth 200 mg/kg Single dose	Peak blood geraniol was only 0.05 +/- 0.01 micrograms/mL at 1 hour. Geranic acid and a glucuronide conjugate of geraniol reached higher levels. Geraniol was found in liver and brain; geranic acid was found in kidney, liver, lung and brain. The authors suggest the metabolites may cause some of the effects attributed to geraniol. Geraniol is converted fast; metabolites reach tissues Methods, limits and funding Outcomes: Blood and tissue levels of geraniol and metabolites Limitations: Mice only; one dose. Funding and conflicts: Not stated in the abstract Read: abstract
Müller 2008 Indoor protection against mosquito and sand fly bites: a comparison between citronella, linalool, and geraniol candles J Am Mosq Control Assoc · PMID 18437831 · DOI	Field experiment	Human landing assays indoors in a high mosquito pressure environment in Israel	Candles with 5% citronella, 5% linalool or 5% geraniol 5% in candles · vs Candles with the other two oils	Repellency against mosquitoes was 29.0% for citronella, 71.1% for linalool and 85.4% for geraniol candles. Against sand flies it was 24.7%, 55.2% and 79.7%. Geraniol candles repelled more than citronella candles in this test Methods, limits and funding Outcomes: Repellency rate against mosquitoes and sand flies Limitations: Candles tested indoors; the abstract gives no untreated baseline or number of volunteers; not comparable with skin repellents. Funding and conflicts: Not stated in the abstract Read: abstract
Mączka 2020 One Hundred Faces of Geraniol Molecules · PMID 32708169 · DOI	Review mixed	Review of uses of geraniol	Geraniol	Describes geraniol as a rose-like monoterpene alcohol used commercially in cosmetic and household products and reports antioxidant and anti-inflammatory properties, activity against several cancer cell types in laboratory and animal studies, and antibacterial activity. Narrative review Methods, limits and funding Outcomes: Uses and biological activities Limitations: Narrative review; mostly lab and animal studies. Funding and conflicts: Authors declare no conflict of interest Read: abstract
Nisar 2024 Geraniol mitigates anxiety-like behaviors in rats by reducing oxidative stress, repairing impaired hippocampal neurotransmission, and normalizing brain cortical-EEG wave patterns after a single electric foot-shock exposure Biomed Pharmacother · PMID 38795639 · DOI	Animal experiment rat	Rats given a single electric foot shock to cause anxiety-like behaviour	Geraniol 10 and 30 mg/kg · vs Diazepam	Geraniol and diazepam reduced anxious behaviour, normalised EEG patterns and brain chemicals, and restored antioxidant levels. Less anxiety-like behaviour in shocked rats Methods, limits and funding Outcomes: Open field, light-dark and social interaction tests; EEG and brain chemistry Limitations: Rats only; a stress model, not an anxiety disorder. Funding and conflicts: Not stated in the abstract Read: abstract
Pavan 2018 Geraniol Pharmacokinetics, Bioavailability and Its Multiple Effects on the Liver Antioxidant and Xenobiotic-Metabolizing Enzymes Front Pharmacol · PMID 29422862 · DOI	Animal experiment rat and mouse	Human intestinal cell model, rats and mice	Geraniol, intravenous or oral 50 mg/kg in rats; 120 mg/kg in mice Single doses in rats; 4 weeks in mice	In rats the blood half-life after an intravenous dose of 50 mg/kg was 12.5 +/- 1.5 minutes. Absolute oral bioavailability of 50 mg/kg was 92% for emulsified geraniol and 16% for fibre-adsorbed geraniol. Geraniol reached the cerebrospinal fluid (0.72 to 2.6 micrograms/mL within 60 minutes). Mice given 120 mg/kg for 4 weeks showed higher antioxidant defences and no signs of liver toxicity; CYP450 enzyme activity was only slightly affected. Geraniol is absorbed well when emulsified and cleared fast; no liver toxicity in mice at 120 mg/kg Methods, limits and funding Outcomes: Absorption, blood half-life, bioavailability and liver effects Limitations: Animals only; doses far above those in everyday exposure; funder not stated in the abstract. Funding and conflicts: Not stated in the abstract Read: abstract
Reeves 2010 Aqueous 2% geraniol as a mosquito repellent failed against Aedes aegypti on ponies J Am Mosq Control Assoc · PMID 21033064 · DOI	Animal experiment horse (ponies)	Ponies, five trials, with mosquitoes held on the skin in tubes	2% aqueous geraniol mist, 60 mL 2% aqueous solution Bites counted 3 hours after spraying · vs Untreated ponies	Bites averaged 56% on untreated ponies and 13% on treated ones, but the difference was not significant (P = 0.081). The authors say 2% geraniol was not an adequate mosquito repellent for horses. No skin irritation was seen. No significant repellent effect at 2% on ponies Methods, limits and funding Outcomes: Percent of mosquito bites Limitations: Very small; wide range in results; ponies, not people. Funding and conflicts: Not stated in the abstract Read: abstract
Ricci 2022 Geraniol Treatment for Irritable Bowel Syndrome: A Double-Blind Randomized Clinical Trial Nutrients · PMID 36235860 · DOI	Controlled trial	56 56 adults with irritable bowel syndrome (Rome III criteria), several Italian centres	Low-absorbable geraniol food supplement, once a day 4 weeks · vs Placebo	IBS-SSS was 195 with geraniol versus 265 with placebo (p = 0.001). Responders (a fall of 50 points or more) were 52.0% with geraniol and 16.7% with placebo (p = 0.009), mainly in the mixed IBS subtype. The gut microbe mix changed. Blood inflammation markers did not differ. More responders with the geraniol supplement (52.0% versus 16.7%) in 56 people Methods, limits and funding Outcomes: IBS symptom severity score (IBS-SSS) and gut microbiota Limitations: Small; one short trial of a special supplement made to reach the lower gut, not food, flowers or essential oil; two authors founded the start-up behind the supplement; dose not given in the abstract. Funding and conflicts: Two authors are founders of Targeting Gut Disease Srl, a university start-up; the company is said to have had no role in analysis Read: abstract
Rizzello 2018 Dietary geraniol ameliorates intestinal dysbiosis and relieves symptoms in irritable bowel syndrome patients: a pilot study BMC Complement Altern Med · PMID 30567535 · DOI	Single arm	People with irritable bowel syndrome (pilot study)	Geraniol by mouth in a delayed-release form that reaches the colon Up to 8 mg per kg body weight per day (maximum) 4 weeks	Symptom scores fell significantly, and the gut microbes Collinsella and Faecalibacterium increased. A blood chemokine called MIP-1 beta fell. The abstract gives no participant number and there was no placebo group. Symptoms improved in a before-and-after pilot Methods, limits and funding Outcomes: IBS symptom score (VAS-IBS), gut microbes and blood chemokines Limitations: No control group; number of participants not stated in the abstract; trial registered retrospectively (2018). Funding and conflicts: Not stated in the abstract Read: abstract
Schwarz 2024 Terpenes from Cannabis sativa induce antinociception in a mouse model of chronic neuropathic pain via activation of adenosine A 2A receptors Pain · PMID 38709489 · DOI	Animal experiment mouse and lab cells	Mice with chemotherapy-induced nerve pain or inflammatory pain; cell and computer studies	Geraniol, linalool, beta-pinene, alpha-humulene, beta-caryophyllene 200 mg/kg ip (100 mg/kg in the morphine combination) · vs Morphine 10 mg/kg; WIN55,212 3.2 mg/kg	The terpenes gave roughly the same pain relief as 10 mg/kg morphine or 3.2 mg/kg WIN55,212. None caused reward in a place-preference test. A low terpene dose combined with a low morphine dose worked better than either alone. A receptor blocker and spinal cord gene knockdown pointed to adenosine A2A receptors, and cell and computer work suggested the terpenes act as agonists there. Pain relief in mice through adenosine A2A receptors Methods, limits and funding Outcomes: Pain thresholds, reward behaviour and receptor mechanism Limitations: Mice; injected at high doses; no human data. Funding and conflicts: Not stated in the abstract Read: abstract
Seekins 2025 Select terpenes from Cannabis sativa are antinociceptive in mouse models of post-operative pain and fibromyalgia via adenosine A(2a) receptors Pharmacol Rep · PMID 39663308 · DOI	Animal experiment mouse	Male and female CD-1 mice with paw-incision pain or reserpine-induced fibromyalgia-like pain	Geraniol, linalool, beta-caryophyllene and alpha-humulene, injected into the abdomen 200 mg/kg ip Pain measured over 3 hours · vs Receptor blocker istradefylline	Terpenes raised the pain threshold in both pain models, strongest for geraniol, then linalool or alpha-humulene. Pre-treatment with the adenosine A2a receptor blocker istradefylline stopped the effect. Hot-plate tests were unchanged, which argues against a general sedative effect. Geraniol had the strongest pain-threshold effect of four terpenes in mice Methods, limits and funding Outcomes: Mechanical pain threshold (von Frey) Limitations: Injected into the abdomen at 200 mg/kg; mice; not a test of smoking or vaping cannabis. Funding and conflicts: Not stated in the abstract Read: abstract
Silva GDSE 2022 Review of anticancer activity of monoterpenoids: Geraniol, nerol, geranial and neral Chem Biol Interact · PMID 35661738 · DOI	Review mixed	Review of anticancer studies of geraniol, nerol, geranial and neral	Geraniol, nerol, geranial, neral	The review says geraniol has been widely explored as a potential anticancer agent and covers synergy with other drugs and new analogues. The abstract gives no numbers. Narrative review of lab and animal work Methods, limits and funding Outcomes: Anticancer activity and synergy with other compounds Limitations: Abstract gives no results; lab and animal work, not treatment evidence. Funding and conflicts: Not stated in the abstract Read: abstract
Singh 2024 Unlocking the therapeutic potential of Geraniol: an alternative perspective for metabolic disease management Inflammopharmacology · PMID 39460887 · DOI	Review mixed	Review of preclinical work on metabolic disease	Geraniol	Reports lipid-lowering, antioxidant and anti-inflammatory effects and better endothelial function in animal studies, and discusses nano-formulations that raise absorption. Narrative review of animal work Methods, limits and funding Outcomes: Diabetes, obesity, heart and blood-fat outcomes in animals Limitations: Preclinical studies only. Funding and conflicts: Not stated in the abstract Read: abstract
Singulani 2018 Geraniol and linalool anticandidal activity, genotoxic potential and embryotoxic effect on zebrafish Future Microbiol · PMID 30480459 · DOI	Laboratory research human cells and zebrafish	Candida yeasts, human cells (micronucleus test) and zebrafish embryos	Geraniol and linalool Geraniol 800 micrograms/mL damaged chromosomes	Both inhibited Candida, geraniol more. Geraniol at 800 micrograms/mL increased chromosome damage. Geraniol was more toxic to zebrafish embryos than linalool: LC50 31.3 versus 193.3 micrograms/mL. Anti-yeast activity, with toxicity at the highest tested concentrations Methods, limits and funding Outcomes: Anti-yeast activity, genotoxicity, embryo toxicity Limitations: Lab and fish embryos; very high concentrations. Funding and conflicts: Not stated in the abstract Read: abstract
Sinha 2014 Evaluation of toxicity of essential oils palmarosa, citronella, lemongrass and vetiver in human lymphocytes Food Chem Toxicol · PMID 24650756 · DOI	Laboratory research human cells	Human lymphocytes in the lab	Palmarosa, citronella, lemongrass and vetiver essential oils; citral and geraniol	The four oils and citral caused cell toxicity and DNA damage at higher concentrations and oxidative stress. Apart from geraniol, apoptosis was confirmed at higher concentrations. The authors judged the oils safe for human consumption at low concentrations. Toxic to human blood cells in a dish at higher concentrations Methods, limits and funding Outcomes: Cytotoxicity, DNA damage and apoptosis Limitations: Lab study; concentrations are not comparable with real exposure. Funding and conflicts: Not stated in the abstract Read: abstract
US Food and Drug Administration 2026 US Code of Federal Regulations Title 21, section 182.60: Synthetic flavoring substances and adjuvants eCFR API (text version dated 2026-10-22, retrieved 2026-10-25) · Source	Authoritative guidance n/a	n/a	n/a	Section 182.60 lists "Geraniol (3,7-dimethyl-2,6 and 3,6-octadien-1-ol)" and "Geranyl acetate (geraniol acetate)" among synthetic flavoring substances and adjuvants that are generally recognized as safe for their intended use, within the meaning of section 409 of the Act. n/a Methods, limits and funding Outcomes: Whether geraniol is on the FDA list of flavouring substances generally recognised as safe Limitations: Reading of a public record on the date given; says nothing beyond its wording. Funding and conflicts: n/a Read: full text
US National Library of Medicine (PubChem) 2026 PubChem compound record for geraniol: CID 637566 PubChem REST API (retrieved 2026-10-25) · Source	Authoritative guidance n/a	n/a	n/a	CID 637566: Geraniol, IUPAC name (2E)-3,7-dimethylocta-2,6-dien-1-ol, formula C10H18O, molecular weight 154.25, InChIKey GLZPCOQZEFWAFX-JXMROGBWSA-N. The synonym list includes CAS 106-24-1, trans-geraniol, (E)-geraniol and geranyl alcohol. n/a Methods, limits and funding Outcomes: Identity, formula, IUPAC name and CAS number of geraniol Limitations: Reading of a public record on the date given; says nothing beyond its wording. Funding and conflicts: n/a Read: full text
Verešová 2024 Chemical Composition, Biological Activity, and Application of Rosa damascena Essential Oil as an Antimicrobial Agent in Minimally Processed Eggplant Inoculated with Salmonella enterica Foods · PMID 39593995 · DOI	Lab analysis plant	One Rosa damascena essential oil	Rose essential oil	The oil was mainly phenylethyl alcohol (70%), with nerol, citronellol and geraniol also significant (the abstract gives no geraniol percent). Geraniol is a smaller part of this rose oil Methods, limits and funding Outcomes: Composition by GC-MS Limitations: No geraniol percentage in the abstract. Funding and conflicts: Not stated in the abstract Read: abstract
Verma 2011 Volatile constituents of essential oil and rose water of damask rose (Rosa damascena Mill.) cultivars from North Indian hills Nat Prod Res · PMID 21711177 · DOI	Lab analysis plant	Damask rose (Rosa damascena) oil and rose water from Indian hills	Rose oil and rose water volatiles Flowers	Rose water volatiles contained phenyl ethyl alcohol (66.2% to 79.0%), geraniol (3.3% to 6.6%) and citronellol (1.8% to 5.5%). The essential oil of cultivar 'Noorjahan' from two sites contained citronellol (15.9% to 35.3%) and geraniol (8.3% to 30.2%). Geraniol was 8.3% to 30.2% of two rose oils Methods, limits and funding Outcomes: Chemical composition Limitations: One cultivar group and region; composition depends on growing site and bloom stage. Funding and conflicts: Not stated in the abstract Read: abstract
Ye 2019 Geraniol targets K(V)1.3 ion channel and exhibits anti-inflammatory activity in vitro and in vivo Fitoterapia · PMID 31669719 · DOI	Animal experiment mouse and human cells	Cells expressing the KV1.3 ion channel, activated human T cells and mice with a psoriasis-like skin condition	Geraniol	Geraniol blocked the KV1.3 channel with an IC50 of about 490 micromolar, reduced release of IL-2, TNF-alpha and IFN-gamma from activated human T cells, and in imiquimod-treated mice lowered the psoriasis severity score. Anti-inflammatory effect in cells and mice Methods, limits and funding Outcomes: Ion channel block, cytokine release, psoriasis score Limitations: The effective concentration is high; mouse skin model. Funding and conflicts: Not stated in the abstract Read: abstract
Younis 2024 Geraniol Ameliorates Pentylenetetrazol-Induced Epilepsy, Neuroinflammation, and Oxidative Stress via Modulating the GABAergic Tract: In vitro and in vivo studies Drug Des Devel Ther · PMID 39654600 · DOI	Animal experiment mouse and lab cells	PC12 nerve cells injured with glutamate, and mice given pentylenetetrazol to cause seizures (kindling)	Geraniol Cells: 25 to 400 micrograms/mL; mice: two doses (100 and 200, units not given in the abstract) · vs Sodium valproate	Geraniol reduced glutamate-induced injury in nerve cells and, in mice, raised GABA, lowered inflammation and oxidative-stress markers consistent with the authors' idea that it works through GABA signalling. Geraniol up to 400 micrograms/mL did not damage the cells. Anti-seizure-like effects in a mouse model Methods, limits and funding Outcomes: Nerve cell injury, GABA signalling, inflammation markers and seizures Limitations: Mouse and cell work. Funding and conflicts: Not stated in the abstract Read: abstract
Yu 2026 Geraniol induces apoptosis in gastric cancer cells by inhibiting the Wnt/β-catenin pathway J Pharm Pharmacol · PMID 41934234 · DOI	Animal experiment human cells and mouse	Human gastric cancer cell lines (SGC-7901, MKN45) and mouse xenografts	Geraniol	Geraniol reduced viability of gastric cancer cells and arrested them in G0/G1, increased apoptosis and lowered the signalling protein beta-catenin in cells and in xenografts. The abstract gives no doses. Laboratory and mouse effect in gastric cancer cells Methods, limits and funding Outcomes: Cell viability, cell death and Wnt/beta-catenin signalling Limitations: Cell lines and mouse grafts only. Funding and conflicts: Not stated in the abstract Read: abstract

What we do not know yet

What the evidence supports: everything for pure geraniol is low, very-low or insufficient certainty. The only human trials are two small studies of one gut supplement.
No trial tested pure geraniol for pain, anxiety, seizures, diabetes, inflammation or infection in people.
No human test of whether geraniol changes the effects of THC or CBD, and no data on geraniol from vapes, edibles or flower.
No human interaction study with prescription drugs; no data in pregnancy, breastfeeding, children or older adults.
The EU fragrance-allergen labelling rules and EFSA flavouring opinions for geraniol were not read.
Our lab data come from one table with an unverified unit and single batches; no regulator or multi-sample data for geraniol were found.

How new research is added

New studies are found by a saved PubMed search and are placed in a review queue. A person reads each one before it changes any evidence rating or safety wording. New publications never change ratings automatically.

Lab markers

What changed in blood or saliva tests during trials. A changed number is not the same as feeling or being healthier, and we give no "normal ranges".

Other 12

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Mechanical pain threshold in mice (von Frey test)

Raised in trials

How hard a thin fibre must press on a mouse paw before the mouse pulls it away. A higher threshold means less sensitivity to touch pain.

Very low certainty

Results and what it means

Why it was measured

It is the standard animal test for nerve and post-surgery pain.

Statistical vs. clinical meaning

An animal pain signal that has not been tested in people.

Safety implication

Not assessed.

Study	Result	People	Product
³²	Geraniol raised the threshold in post-operative and fibromyalgia-like pain, strongest of four terpenes; an adenosine A2a blocker stopped it.	CD-1 mice	200 mg/kg injected into the abdomen
³¹	Terpenes gave roughly the same relief as 10 mg/kg morphine in chemotherapy-induced nerve pain.	Mice	200 mg/kg injected

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CB1 receptor activation in cells

Raised in trials

Whether a molecule switches on the CB1 receptor, the main brain receptor for THC and for the body's own cannabinoids.

Not enough evidence

Results and what it means

Why it was measured

To see whether cannabis terpenes act directly on the cannabinoid system.

Statistical vs. clinical meaning

A laboratory signal only; the strength is not given in the abstract.

Safety implication

Not assessed.

Study	Result	People	Product
¹⁹	All terpenes tested, including geraniol, activated CB1 in cells.	Cells in the lab	Terpenes in cell assays

¹⁹

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Anxiety-like behaviour in rats (open field, light-dark, social interaction)

Lowered in trials

Animal tests that count how much a rat explores open or bright spaces and interacts with other rats.

Very low certainty

Results and what it means

Why it was measured

They are the usual first screening tests for anxiety-reducing molecules.

Statistical vs. clinical meaning

A signal in one model.

Safety implication

Not assessed.

Study	Result	People	Product
²⁶	Geraniol 10 and 30 mg/kg and diazepam reduced anxious behaviour and normalised EEG.	Rats after foot shock	Geraniol 10 and 30 mg/kg versus diazepam

²⁶

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Brain damage area (infarct) after blood-flow loss in rats

Lowered in trials

The size of dead tissue seen on stained brain slices after blood supply is cut and restored.

Very low certainty

Results and what it means

Why it was measured

Smaller damage suggests protection in the model.

Statistical vs. clinical meaning

One rat model.

Safety implication

Not assessed.

Study	Result	People	Product
³	Geraniol pre-treatment reduced infarct area and protected hippocampal CA1 neurons.	Rats with 30 minutes of blood-flow occlusion	Geraniol before injury

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GABA level in nerve cells and mouse brain

Raised in trials

GABA is the brain's main calming chemical messenger.

Not enough evidence

Results and what it means

Why it was measured

Many anti-seizure drugs raise GABA signalling.

Statistical vs. clinical meaning

A lab signal in one study.

Safety implication

Not assessed.

Study	Result	People	Product
⁴²	Geraniol raised GABA and GABA-making enzymes in cells and in mice with chemically induced seizures.	PC12 cells and mice	Geraniol

⁴²

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IBS symptom severity score (IBS-SSS)

Lowered in trials

A questionnaire score of how severe irritable bowel symptoms are. A fall of 50 points or more is counted as a response.

Low certainty

Results and what it means

Why it was measured

It is the usual outcome in IBS trials.

Statistical vs. clinical meaning

A symptom drop larger than placebo in one small trial.

Safety implication

Side effects not reported in the abstracts.

Study	Result	People	Product
²⁹	195 with geraniol versus 265 with placebo (p = 0.001); responders 52.0% versus 16.7% (p = 0.009).	56 adults with IBS	Low-absorbable geraniol supplement versus placebo, 4 weeks
³⁰	VAS-IBS symptom scores fell significantly (no placebo group).	People with IBS (pilot)	Delayed-release geraniol up to 8 mg/kg/day, 4 weeks

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Gut microbes (Faecalibacterium, Oscillospira)

Mixed results in trials

Faecalibacterium is a gut microbe that makes the fatty acid butyrate and is often low in IBS. Oscillospira is another genus.

Low certainty

Results and what it means

Why it was measured

To see whether the supplement changes the gut microbe mix.

Statistical vs. clinical meaning

Microbe changes are a lab marker, not a symptom; the Faecalibacterium change was only a trend in the trial.

Safety implication

Not described.

Study	Result	People	Product
²⁹	Oscillospira fell significantly (p = 0.01) and Faecalibacterium showed an increasing trend (p = 0.09).	56 adults with IBS	Geraniol supplement versus placebo
³⁰	Collinsella and especially Faecalibacterium rose.	People with IBS (pilot)	Delayed-release geraniol

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Tumour growth in mice with grafted or induced cancers

Lowered in trials

How fast tumours grow in mice that carry human cancer cells or induced tumours.

Not enough evidence

Results and what it means

Why it was measured

It is a first screen for anti-cancer effects in animals.

Statistical vs. clinical meaning

A mouse and cell result only.

Safety implication

Cell and DNA damage was seen in healthy human blood cells at higher concentrations in another study.

Study	Result	People	Product
⁶	Tumour growth fell; with 5-fluorouracil, more than 82% inhibition.	Mice with breast carcinoma	Geraniol alone and with 5-fluorouracil
¹⁸	Geraniol and low-dose docetaxel suppressed tumour growth in PC-3 prostate xenografts.	Mice with grafted PC-3 cells	Geraniol with docetaxel
⁴³	Lower viability and more apoptosis in gastric cancer cells and xenografts.	Gastric cancer cells and xenografts	Geraniol

^{6 18 43 36}

↕

Blood fats and liver and kidney function in diabetic rats

Mixed results in trials

Blood cholesterol and fat levels and markers of liver and kidney damage.

Very low certainty

Results and what it means

Why it was measured

Diabetes damages organs, so these markers show protection in the model.

Statistical vs. clinical meaning

A rat result only.

Safety implication

Not assessed.

Study	Result	People	Product
⁵	Lipid profile and liver and kidney function improved; antioxidant enzymes rose; Casp3 and Bax mRNA fell.	Rats with HFD/STZ diabetes	Geraniol 100 and 200 mg/kg, 6 weeks

⁵

▼

Immune messengers IL-2, TNF-alpha and IFN-gamma from human T cells

Lowered in trials

Signalling proteins that activated immune cells release.

Very low certainty

Results and what it means

Why it was measured

High levels are linked to autoimmune inflammation.

Statistical vs. clinical meaning

A laboratory result at a high concentration.

Safety implication

Not assessed.

Study	Result	People	Product
⁴¹	Geraniol lowered the release of IL-2, TNF-alpha and IFN-gamma from activated human T cells at concentrations that block KV1.3.	Human T cells in the lab	Geraniol; IC50 for KV1.3 about 490 micromolar

⁴¹

▼

MRSA biofilm formation (lab)

Lowered in trials

Biofilm is a sticky bacterial layer that protects the bacteria from antibiotics.

Very low certainty

Results and what it means

Why it was measured

Biofilm makes infections hard to clear.

Statistical vs. clinical meaning

A lab and mouse result.

Safety implication

Toxic to zebrafish embryos at 31.3 micrograms/mL (LC50) in another study.

Study	Result	People	Product
⁷	Biofilm formation fell by 86.13% at 256 micrograms/mL and mature biofilm by 49.87%.	MRSA USA300 in the lab	Geraniol 256 micrograms/mL

^{7 35}

↕

Mosquito and sand fly bites (repellency rate)

Mixed results in trials

The share of bites prevented compared with no repellent.

Mixed findings

Results and what it means

Why it was measured

It is the standard way to test repellents.

Statistical vs. clinical meaning

One favourable and one non-significant test.

Safety implication

No skin irritation in ponies; geraniol can cause allergy in some people.

Study	Result	People	Product
²⁴	Repellency against mosquitoes 85.4% with geraniol candles, 29.0% with citronella.	Human volunteers indoors	5% candles
²⁸	Bites 13% on treated ponies versus 56% on untreated, not significant (P = 0.081).	Ponies	2% aqueous geraniol mist

^{24 28}

Safety

What studies and official sources say about side effects, medicines and who should check first. Each point shows what kind of evidence it comes from.

Main points to know 6

Geraniol that has reacted with air is a common skin allergen. Pure geraniol is a weak skin allergen, but geraniol that has sat in air forms stronger ones (mainly geranial and neral, plus a hydroperoxide). Skin enzymes can make the same allergens from geraniol. In Swedish dermatitis clinics, patch tests with oxidised geraniol were positive in 0.55% of 2,179 patients at 2% (2012), in 3% of 1,476 patients at 6% and 8% at 11% (2018, with pure geraniol 1%), and in 5.8% at 11% in a later series (2024). Pure geraniol alone detected far fewer, and the authors say it is of little value as a test. These are people already seen for rashes, and high test strengths can include some irritation, so the rate in the general public is lower. Geraniol is part of fragrance mix I, a standard patch test. Observational ^{10 11 13 14 2}
How geraniol turns into an allergen. In mouse skin-allergy tests, air-exposed geraniol was a moderate sensitiser, quite different from pure geraniol. Geranial, neral and 6,7-epoxygeraniol were moderate sensitisers and 6,7-epoxygeranial a strong one. The authors say geraniol is activated both by air and by skin enzymes (CYP1A1 and CYP3A5 likely). A fragrance bottle or oil that has been open for a long time is therefore a bigger concern than a fresh one. Animal research ^{8 9}
Allergy to geraniol overlaps with allergy to citral. Among patients who reacted to citral (which is geranial plus neral), 26% reacted to oxidised geraniol in one series and 61% in another. Geranial was the main shared allergen. Citral and its parts gave positive reactions in 25% of patients who reacted to pure geraniol. Someone allergic to one fragrance may therefore react to the other, and to lemongrass-type oils that are rich in citral. Observational ^{12 14}
The fragrance industry's own safety review. The expert panel of the fragrance industry's research institute (RIFM, 2022) reports that geraniol is not genotoxic, that margins of exposure for repeated-dose and reproductive toxicity are above 100, that it is not expected to be phototoxic, and that it has a skin-sensitisation threshold (NESIL) of 11,000 micrograms per square centimetre. It concludes that current fragrance use is supported. The panel is paid by the industry that sells the ingredient, and it does not replace independent regulators. Authoritative guidance ¹
Cannabis flower holds very little geraniol, and no one has tested vaping it. In our lab data geraniol is a tiny part of cannabis flower. No human study was found on breathing geraniol from vaped or smoked cannabis, on geraniol in edibles, or on geraniol as a cannabis supplement. Gap
Toxic to cells and fish embryos at high concentrations. Geraniol damaged chromosomes in human cells at 800 micrograms/mL and was toxic to zebrafish embryos (LC50 31.3 micrograms/mL). Human blood cells in a dish were harmed by palmarosa, citronella and lemongrass oils and by citral at higher concentrations. These are lab concentrations, not exposure from products, but they are a reason not to swallow or inject concentrated geraniol or essential oils. Laboratory research ^{35 36}

Side effects 5

Effect	How often	Severity and recovery	Evidence
Allergic contact dermatitis (itchy, red, sometimes blistering rash) from geraniol, mostly oxidised geraniol The rates are for people already in skin clinics, not the general public.	In patch-tested dermatitis patients: 0.13% to 1% for pure geraniol and 0.55% to 8% for oxidised geraniol, depending on the test strength (6% and 11% in petrolatum gave 3% and 8%).	moderate Not described in the abstracts	Observational ^{10 11 13 2}
Skin irritation from geraniol itself Small tests with a few people or animals.	Neither pure nor oxidised geraniol gave significant irritant reactions in 27 patients at 2.5% to 20% in one test; 2% geraniol caused no skin irritation in ponies.	mild Not described	Observational ^{11 28}
Reactions in people who are already allergic to citral Mostly due to geranial.	26% of citral-positive patients reacted to oxidised geraniol in one series and 61% in another.	moderate Not described	Observational ^{12 14}
Side effects of the IBS geraniol supplement Two small studies of one supplement; absence of a report is not proof of safety.	Not reported in either abstract.	unknown Not described	Controlled trial ^{29 30}
Possible harm to cells and embryos at very high concentrations (lab only) Not a measure of risk from fragrance or food use.	Chromosome damage at 800 micrograms/mL; zebrafish embryo LC50 31.3 micrograms/mL.	unknown in people Not applicable	Laboratory research ³⁵

Liver

No human case of liver injury from geraniol was found in the sources read, and LiverTox was not read. In mice given 120 mg/kg a day for 4 weeks, geraniol raised antioxidant defences with no signs of liver toxicity, and drug-handling CYP450 enzymes were only slightly affected. Rats absorbed an emulsified oral dose well (92% bioavailability) and cleared it fast (blood half-life 12.5 minutes after an injection). In three human volunteers, geraniol was turned into acids (Hildebrandt acid, geranic acid) in about 2 to 4 hours and passed in urine. ^{27 16 23}

How often. No human rate was found.

Monitoring. No agency monitoring advice was read.

This is a safety connection. It is not evidence that Geraniol supports liver health.

Medicines and supplements 5

With	Why it matters	Importance	Evidence	What to do
Prescription drugs handled by CYP enzymes (CYP450 family) prescription	In mice, 120 mg/kg a day for 4 weeks only slightly changed CYP450 enzyme activity. Skin enzymes CYP1A1 and CYP3A5 turn geraniol into allergens in lab tests. No human interaction study was found.	Unknown in people.	Animal research Very low certainty ^{27 9}	Tell your doctor or pharmacist about any geraniol supplement or essential oil you take by mouth.
THC, CBD and other cannabinoids cannabis	In mice, geraniol injected with a lab cannabinoid drug (WIN55,212) had additive cannabinoid-like effects, and in cells geraniol activated the CB1 receptor. This was not tested with THC or in people.	Unknown; the amounts of geraniol in cannabis flower in our data are very small.	Animal research Not enough evidence ¹⁹	Do not assume geraniol-rich strains or products are stronger or calmer. Ask a doctor if you take medicines and use cannabis.
Morphine and other opioid painkillers prescription	In mice a low terpene dose (100 mg/kg) with a low morphine dose (3.2 mg/kg) gave stronger pain relief than either alone. No human data.	Unknown in people.	Animal research Not enough evidence ³¹	Ask a doctor before combining any terpene supplement with painkillers.
Chemotherapy (docetaxel, 5-fluorouracil) prescription	In cells and mice geraniol increased the effect of docetaxel and 5-fluorouracil on tumours. This is lab and animal work and shows no benefit or harm in patients.	Unknown in people; the same effect might raise toxicity.	Animal research Not enough evidence ^{18 6}	Do not take geraniol supplements or oils during cancer treatment without asking your oncologist.
Other fragrance allergens (citral, limonene, linalool) and ketoprofen gel other	Contact allergy to oxidised geraniol often goes with citral allergy. Patients with photoallergy to the painkiller gel ketoprofen had more reactions to oxidised geraniol 11% than expected (four patients).	Matters for people who already have fragrance or ketoprofen skin allergy.	Observational Low certainty ^{12 2}	If you have a known fragrance allergy, check labels for geraniol.

Who should check first 6

Situation	Advice	Evidence
Known fragrance, geraniol, citral or rose/geranium oil skin allergy, or hand and face dermatitis	Avoid products that list geraniol or geranium, rose or lemongrass oil if they irritate your skin. Stop use and ask a clinician if a product makes the skin itch or blister.	Observational ^{13 14}
Pregnancy and breastfeeding	No human safety data on geraniol supplements or concentrated geraniol in pregnancy or breastfeeding were found, and LactMed and EFSA documents were not read. Ask your doctor before using geraniol supplements, essential oils or cannabis products.	Gap
Children, teens and older adults	No trial of geraniol in these groups was found. Keep essential oils and terpene liquids away from children.	Gap
Driving, work with machinery and impairment	No human impairment data for geraniol were found. In mice, hot-plate tests were unchanged after injected geraniol, which does not show absence of impairment. THC-containing cannabis impairs driving: see the THC page.	Gap ³²
Mental health: THC-related psychosis, anxiety and dependence	This page is about geraniol, not THC. No source read links geraniol to psychosis, dependence or cannabis hyperemesis syndrome. If you use cannabis, read the THC page for those risks.	Gap
Cancer treatment or planning to replace treatment	Geraniol has been studied in cancer cells and mice only. It is not a substitute for medical care.	Preclinical ³³

Overdose, product quality and regulators

Summary. The sources read do not include a full toxicology review. What they show: geraniol is not genotoxic in the industry panel's reading (2022); at lab concentrations of 800 micrograms/mL it damaged chromosomes and killed fish embryos; mice given 120 mg/kg a day for 4 weeks showed no signs of liver toxicity; and the major human risk is skin allergy from oxidised geraniol. The FDA lists geraniol among flavouring substances generally recognised as safe in food.

Animal. Mice: 120 mg/kg for 4 weeks, no liver toxicity signs. Mice and rats were also given 100 to 200 mg/kg in disease models with no toxicity reported in the abstracts. Zebrafish embryo LC50 31.3 micrograms/mL. No LD50 figures were read.

Human doses studied. Single oral doses of 25 mg and 250 mg in three volunteers (metabolism study); up to 8 mg/kg a day for 4 weeks in a delayed-release supplement in a pilot IBS study; a low-absorbable supplement once a day for 4 weeks in the IBS trial. These describe what studies gave, not advice. Dietary intake was estimated at about 1.43 mg a day in adults without work exposure (from urine).

High dose or long term signals. No long-term human data on geraniol by mouth or by inhalation were found.

Overdose response. Not described in the sources read.

Genotoxicity. The RIFM panel (2022) reports geraniol is not genotoxic; a lab micronucleus test at 800 micrograms/mL found chromosome damage; human lymphocytes showed no apoptosis with geraniol in a 2014 study, though DNA damage was reported for the oils and citral.

Geraniol can come from the plant or be made industrially and added to products. Oxidation on the shelf matters for skin safety. No study we read tested whether geraniol numbers on cannabis labels are accurate.

Oxidation on the shelf. Air-exposed geraniol forms strong allergens (geranial, neral and a hydroperoxide). Oxidised geraniol was a better marker of allergy than pure geraniol in patch tests. ^{8 11}

Adulterated rose products. Of ten rose waters bought in Shiraz, some had Pelargonium and Dianthus oils or synthetic essences added, and most contained dibutyl phthalate. A rose or geranium label does not guarantee the content. ²²

Large differences between oils. Geraniol made up 8.3% to 30.2% of two rose oils, 14.6% of one geranium oil, and 37.1% or more of single citronella and lemongrass samples in Nepal, while other Cymbopogon oils were mainly citral. Amounts vary by plant, part, site and batch. ^{40 17 4}

Cannabis batch variation. Our lab numbers are single batches. The same strain name had a three-fold spread between two samples (for example Jabberwocky) in the same table.

Body	Action	Date
US Food and Drug Administration (Code of Federal Regulations, Title 21, section 182.60) (United States)	Section 182.60 lists "Geraniol (3,7-dimethyl-2,6 and 3,6-octadien-1-ol)" and geranyl acetate among synthetic flavoring substances and adjuvants that are generally recognized as safe for their intended use as food flavourings. source	2026-10-25

When to get medical help

A child or adult swallowed concentrated geraniol, rose, geranium, citronella or lemongrass oil, or a terpene liquid, and is coughing, choking, very drowsy or has trouble breathing (get emergency help and call a poison centre).
A rash that spreads quickly, blisters, or swelling of the face or lips after skin contact with a perfume, cream or oil that contains geraniol.
Trouble breathing, chest tightness or wheezing after breathing a spray or vapour, especially in someone with asthma.
Severe anxiety, confusion or loss of touch with reality after using cannabis products (see the THC page).
Using a geraniol supplement or oil instead of medical treatment for cancer, infection or another serious illness.

Stop using the product and contact a clinician or emergency service. In the US, Poison Control is 1-800-222-1222.

General information only, not medical advice. Ask a clinician or pharmacist before use, especially with medicines, in pregnancy or with a health condition. See the Natural Remedy Safety guide.

Frequently asked questions

What is geraniol?

Geraniol is a rose-smelling molecule made by plants such as rose and geranium, and by cannabis in tiny amounts. It is a terpene alcohol with the formula C10H18O.

^{38 25}

Which plants contain geraniol?

Rose oil (8.3% to 30.2% in two oils), rose-scented geranium (14.6% in one oil) and some lemongrass-type oils. In one Nepal study geraniol was 37.1% of a citronella fraction and 76.6% of lemongrass leaf oil, though citral is normally the main compound in these grasses. Amounts vary by plant and batch.

^{40 17 4}

How much geraniol is in cannabis?

Very little in our data. We have 20 single-batch measurements for 18 strains, from 0.0000657 to 0.000486 as printed in one published table (unit not independently verified). The same strain name varied more than threefold between samples.

Can geraniol cause a skin allergy?

Yes, mainly once it has reacted with air. In Swedish dermatitis clinics 3% of 1,476 patients reacted to oxidised geraniol at 6% and 8% at 11% in a patch test, against 1% for pure geraniol. These patients were already seen for rashes, so the rate in the general public is lower.

^{13 10 2}

Why does air make geraniol worse?

Air changes geraniol into geranial, neral and a hydroperoxide, which are stronger skin allergens in mouse tests. Skin enzymes can make the same allergens.

^{8 9}

Does geraniol treat cancer?

No. Geraniol slowed prostate, stomach and breast cancer cells in dishes and mice. This is laboratory research with concentrations far above what the body reaches, and there is no human trial. Do not use it in place of medical treatment.

^{18 43 6 33}

Does geraniol relieve pain or anxiety?

Not shown in people. Injected geraniol raised pain thresholds in mice, and reduced anxiety-like behaviour in rats. Those are animal results.

^{32 31 26}

Does geraniol help irritable bowel syndrome?

One small trial (56 adults) of a low-absorbable geraniol supplement found a lower symptom score than placebo after 4 weeks, but two authors founded the company that makes it and it has not been repeated by others. It does not apply to geraniol from food or oils.

^{29 30}

Does geraniol change how THC feels?

Not shown. In mice, injected geraniol had cannabinoid-like and additive effects with a lab cannabinoid drug, and it activated the CB1 receptor in cells. No human study tested it with THC.

¹⁹

Is geraniol safe in food?

The US FDA lists geraniol among flavouring substances generally recognised as safe for use in food flavourings (checked 2026-10-25). That status says nothing about supplements, vaping, skin products or cannabis products. We could not read the EU rules.

³⁷

Is geraniol safe in pregnancy or for children?

No studies of geraniol by itself were found for pregnancy, breastfeeding, children or older adults. Ask your doctor or pharmacist before using geraniol supplements, essential oils or cannabis products.

Is geraniol a good mosquito repellent?

The evidence is mixed. 5% geraniol candles repelled mosquitoes better than citronella candles in one test (85.4% versus 29.0%), but a 2% spray on ponies did not give a significant effect.

^{24 28}

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Editorial transparency

Written by: AlternativeMed editorial team. Research compiled with AI assistance, then checked against PubMed records.
Medical review: None. This page has not been reviewed by a physician or pharmacist.
First published: 2026-10-25
Last substantive update: 2026-10-25
How we research: We searched PubMed and read the abstracts of 41 papers, read the FDA flavouring list through the Electronic Code of Federal Regulations and PubChem for identity. Only abstracts were read for papers. Certainty ratings are the compiler's own reading; no review we read gave a GRADE rating. EUR-Lex (EU rules), EFSA, LiverTox and LactMed were not read. The lab numbers are from a published table, not our own testing.
How we rate evidence: See "How we rate evidence" in the Evidence tab.
Independence: No product is promoted on this page. No affiliate links are shown, and none will be added for geraniol. This page is information, not a recommendation to use it.

Sources 43

Each source was opened and checked. Where we read only the abstract, it says so. The small numbers in the text point here.

Api AM, Belsito D, Botelho D et al.. RIFM fragrance ingredient safety assessment, geraniol, CAS registry number 106-24-1. Food Chem Toxicol. 2022. PMID 35940332. DOI 10.1016/j.fct.2022.113341. (abstract)
Bruze M, Marmgren V, Zimerson E et al.. Contact allergy to oxidised geraniol may be over-represented in individuals with photocontact allergy to ketoprofen. Contact Dermatitis. 2024. PMID 37840237. DOI 10.1111/cod.14437. (abstract)
Buch P, Sharma T, Airao V et al.. Geraniol protects hippocampal CA1 neurons and improves functional outcomes in global model of stroke in rats. Chem Biol Drug Des. 2023. PMID 37118873. DOI 10.1111/cbdd.14260. (abstract)
Dangol S, Poudel DK, Ojha PK et al.. Essential Oil Composition Analysis of Cymbopogon Species from Eastern Nepal by GC-MS and Chiral GC-MS, and Antimicrobial Activity of Some Major Compounds. Molecules. 2023. PMID 36677603. DOI 10.3390/molecules28020543. (abstract)
El Azab EF, Mostafa HS. Geraniol ameliorates the progression of high fat-diet/streptozotocin-induced type 2 diabetes mellitus in rats via regulation of caspase-3, Bcl-2, and Bax expression. J Food Biochem. 2022. PMID 35312192. DOI 10.1111/jfbc.14142. (abstract)
El-Ganainy SO, Shehata AM, El-Mallah A et al.. Geraniol suppresses tumour growth and enhances chemosensitivity of 5-fluorouracil on breast carcinoma in mice: involvement of miR-21/PTEN signalling. J Pharm Pharmacol. 2023. PMID 37379815. DOI 10.1093/jpp/rgad060. (abstract)
Gu K, Ouyang P, Hong Y et al.. Geraniol inhibits biofilm formation of methicillin-resistant Staphylococcus aureus and increase the therapeutic effect of vancomycin in vivo. Front Microbiol. 2022. PMID 36147840. DOI 10.3389/fmicb.2022.960728. (abstract)
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Jäger T, Koch HM, Leibold E et al.. Human Metabolism and Urinary Elimination Kinetics of the Fragrance Geraniol after Oral Dosage. Chem Res Toxicol. 2023. PMID 37921539. DOI 10.1021/acs.chemrestox.3c00206. (abstract)
Kačániová M, Vukic M, Vukovic NL et al.. An In-Depth Study on the Chemical Composition and Biological Effects of Pelargonium graveolens Essential Oil. Foods. 2023. PMID 38201061. DOI 10.3390/foods13010033. (abstract)
Kim SH, Bae HC, Park EJ et al.. Geraniol inhibits prostate cancer growth by targeting cell cycle and apoptosis pathways. Biochem Biophys Res Commun. 2011. PMID 21371438. DOI 10.1016/j.bbrc.2011.02.124. (abstract)
LaVigne JE, Hecksel R, Keresztes A et al.. Cannabis sativa terpenes are cannabimimetic and selectively enhance cannabinoid activity. Sci Rep. 2021. PMID 33859287. DOI 10.1038/s41598-021-87740-8. (abstract)
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Lei Y, Fu P, Jun X et al.. Pharmacological Properties of Geraniol - A Review. Planta Med. 2019. PMID 30308694. DOI 10.1055/a-0750-6907. (abstract)
Moein M, Zarshenas MM, Delnavaz S. Chemical composition analysis of rose water samples from Iran. Pharm Biol. 2014. PMID 24863280. DOI 10.3109/13880209.2014.885062. (abstract)
Moriki Y, Mitsugi R, Kayou T et al.. Pharmacokinetics of Geraniol and Its Metabolites in Mice After Oral Administration. Food Sci Nutr. 2025. PMID 39803254. DOI 10.1002/fsn3.4653. (abstract)
Müller GC, Junnila A, Kravchenko VD et al.. Indoor protection against mosquito and sand fly bites: a comparison between citronella, linalool, and geraniol candles. J Am Mosq Control Assoc. 2008. PMID 18437831. DOI 10.2987/8756-971X(2008)24[150:IPAMAS]2.0.CO;2. (abstract)
Mączka W, Wińska K, Grabarczyk M. One Hundred Faces of Geraniol. Molecules. 2020. PMID 32708169. DOI 10.3390/molecules25143303. (abstract)
Nisar R, Inamullah A, Ghalib AUF et al.. Geraniol mitigates anxiety-like behaviors in rats by reducing oxidative stress, repairing impaired hippocampal neurotransmission, and normalizing brain cortical-EEG wave patterns after a single electric foot-shock exposure. Biomed Pharmacother. 2024. PMID 38795639. DOI 10.1016/j.biopha.2024.116771. (abstract)
Pavan B, Dalpiaz A, Marani L et al.. Geraniol Pharmacokinetics, Bioavailability and Its Multiple Effects on the Liver Antioxidant and Xenobiotic-Metabolizing Enzymes. Front Pharmacol. 2018. PMID 29422862. DOI 10.3389/fphar.2018.00018. (abstract)
Reeves WK, Miller MM. Aqueous 2% geraniol as a mosquito repellent failed against Aedes aegypti on ponies. J Am Mosq Control Assoc. 2010. PMID 21033064. DOI 10.2987/10-6000.1. (abstract)
Ricci C, Rizzello F, Valerii MC et al.. Geraniol Treatment for Irritable Bowel Syndrome: A Double-Blind Randomized Clinical Trial. Nutrients. 2022. PMID 36235860. DOI 10.3390/nu14194208. (abstract)
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Silva GDSE, Marques JNJ, Linhares EPM et al.. Review of anticancer activity of monoterpenoids: Geraniol, nerol, geranial and neral. Chem Biol Interact. 2022. PMID 35661738. DOI 10.1016/j.cbi.2022.109994. (abstract)
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Singulani JL, Pedroso RS, Ribeiro AB et al.. Geraniol and linalool anticandidal activity, genotoxic potential and embryotoxic effect on zebrafish. Future Microbiol. 2018. PMID 30480459. DOI 10.2217/fmb-2018-0200. (abstract)
Sinha S, Jothiramajayam M, Ghosh M et al.. Evaluation of toxicity of essential oils palmarosa, citronella, lemongrass and vetiver in human lymphocytes. Food Chem Toxicol. 2014. PMID 24650756. DOI 10.1016/j.fct.2014.02.036. (abstract)
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