Essential Oils & Aromatherapy · Essential oil
Rosemary Oil
Salvia rosmarinus (also called Rosmarinus officinalis) · also called Rosemary essential oil, rosemary oil
Rosemary oil is the strong, camphor-like oil steam-distilled from the rosemary plant. It is used in diffusers, hair and massage products and cosmetics. Evidence is small and mixed: one hair-loss trial, a few scent trials on alertness, memory and anxiety. The main caution: never swallow it, because it contains camphor, and people with epilepsy, children and pregnant women should avoid it unless a doctor agrees.
General information, not medical advice. Last substantive update · Not medically reviewed. A named clinician has not signed off on this page. How this page is made
About Rosemary Oil
Rosemary oil is best known as a stimulating, camphor-like scent and a hair-care ingredient. Small trials suggest it may lower sleepiness and, in one trial, match a weak minoxidil for hair counts, but the evidence is thin and mixed. The oil should never be swallowed, can trigger skin and breathing reactions, and contains camphor, which is linked to seizures when swallowed.
What rosemary oil is
Rosemary oil is the essential oil steam-distilled from the above-ground parts of rosemary, a Mediterranean shrub in the mint family. Its accepted name is Salvia rosmarinus; most trials use the older name Rosmarinus officinalis.
The main compounds are 1,8-cineole, camphor and alpha-pinene. The European Pharmacopoeia accepts different chemical types: one with about 16 to 25 percent cineole and 13 to 21 percent camphor, another with 38 to 55 percent cineole and 5 to 15 percent camphor. A trial on one type does not carry over to another.
What people use it for, and how strong the evidence is
Smelled in small trials: lower sleepiness in 80 nurses (low certainty), better memory quality but slower memory speed in 144 healthy adults (low), mixed results for anxiety before surgery and exams, and very thin results for memory and sleep in older or ill people.
On the scalp: one 6-month trial of 100 people found hair counts rose with rosemary oil about as much as with 2% minoxidil. There was no placebo group and nothing changed at 3 months. Reviews call the evidence limited.
Other results are thin or null: a 26-person pain experiment, a 12-person pilot for cold hands, and no change in lung function in 106 healthy people. Traditional uses for aches and leg circulation are accepted by the EU on long use only, with no clinical trials.
The research in one view
We read the abstracts of 23 PubMed papers and the EMA, Poison Control and ASPCA pages. Most trials are small, short and cannot hide the smell, so expectations shape results. We found no large, independent trial of rosemary oil for any use.
A 2019 seizure review has an author with an essential oil company affiliation, which is flagged here. Where a source covered the leaf, extracts or several oils together, we said so.
Oil, leaf, tea and extracts are different things
EMA treats rosemary oil as a skin medicine and the leaf as a tea and bath product, with different warnings. Results for the leaf or extracts do not carry over to the oil, and a result for one oil type may not carry over to another.
What regulators say
EMA's herbal committee accepts rosemary oil skin medicines for minor muscle and joint pain and minor leg circulation problems on traditional use only. It says do not use under 18, in pregnancy or breastfeeding, with allergy, or with heart or kidney disease. Its assessment report notes there are no clinical studies for these uses and not enough data for a European list entry.
Poison Control gives general essential oil warnings and does not name rosemary oil.
At a glance
Traditional uses history, not proof
- Valued as a tonic and memory aid in ancient Greece and Rome (EMA assessment report).
- Hair tonic and bath or rub oil in folk medicine (EMA assessment report).
- Skin medicines for minor muscle and joint aches and minor leg circulation problems, accepted in the EU on long-standing use only (EMA).
Studied for research
- Alertness and sleepiness, smelled oil, low
- Memory in healthy adults, smelled oil, low
- Memory in older or ill people, very low
- Anxiety before surgery and exams, mixed
- Sleep quality, very low
- Hair loss, scalp use, low
- Pain, Raynaud's phenomenon, breathing tests, insufficient to low
Main compounds
- 1,8-Cineole, a main component
- Camphor, a main component and the seizure concern when swallowed
- Alpha-pinene, a main component
Common forms
- Essential oil (steam-distilled above-ground parts)
- Licensed skin creams in the EU (traditional use)
- Hair and scalp products, massage oils and fragranced cosmetics
- Rosemary leaf, tea and extracts (different products)
Research links: EMA: Rosemary oil herbal summary · EMA assessment report (oil and leaf) · Poison Control: Essential oils · ASPCA: Rosemary (plant) · Rosemary oil vs minoxidil 2% trial (abstract) · Essential oils and seizures: systematic review (abstract) · Research Library · Genes & Biomarkers Library
What it is and its history
- Accepted scientific name
- Salvia rosmarinus
- Naming authority
- Spenn.
- Synonyms
- Name: Rosmarinus officinalis; Authority: L.; Note: The older and still widely used name, including by EMA and in most trials. GBIF lists it as a synonym.
- Common names
- Rosemary (English); Rosemary oil (English); Romero (aceite esencial de romero) (Spanish)
- Family or group
- Lamiaceae (mint family), per GBIF and the EMA assessment report.
- Classification
- Plantae > Tracheophyta > Magnoliopsida > Lamiales > Lamiaceae > Salvia > Salvia rosmarinus
- Native range
- Not checked.
- Habitat
- Not checked.
- What it looks like
- Part used: The oil is steam-distilled from the above-ground parts of the plant (European Pharmacopoeia definition quoted by EMA). This page does not describe how to recognise the plant.
- Look-alikes and adulterants
- Name: Bog rosemary (Andromeda) and wild or March rosemary (Ledum palustre); Note: EMA says these are in the heather family (Ericaceae) and not related to rosemary. Oils sold under similar names should not be assumed to be rosemary.
- Sustainability and conservation
- Not checked (no IUCN or CITES source read).
Traditional use and history history, not clinical proof
| Tradition or era | Documented use | Source |
|---|---|---|
| Ancient Greece and Rome | The EMA assessment report says rosemary oil was valued in ancient Greece and Rome as a tonic, stimulant and carminative, and for indigestion, headache, nervous tension and to strengthen the memory. In the Middle Ages it was distilled for medicine. | EMA assessment report (history section) |
| Folk medicine in different regions | The same report lists traditional claims for rosemary as a hair tonic against baldness, an antiseptic, for colds and rheumatic pain, and, in Brazilian folk medicine, for menstrual complaints and as an abortive agent. These are traditional claims; the oil itself has not been proven for them. | EMA assessment report (history section) |
| European herbal medicine today | The EU accepts rosemary oil skin medicines for minor muscle and joint pain and minor leg circulation problems on the basis of at least 30 years of use (15 in the EU), not on trials. | EMA public summary and monograph |
Traditional use shows how it was used. It does not show that it 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 |
|---|---|---|---|---|
| 1,8-Cineole (eucalyptol) PubChem 2758 | monoterpene ether | Steam-distilled oil from above-ground parts Pharmacopoeia ranges quoted by EMA: about 16 to 25 percent in the Spanish type and 38 to 55 percent in the Moroccan and Tunisian type. | Absorbed into the blood when the aroma is breathed in (human study). Named with camphor as a seizure-linked compound when oils are swallowed (review). 25 8 20 3 | Human observational |
| Camphor PubChem 2537 | bicyclic monoterpene ketone | Steam-distilled oil from above-ground parts About 13 to 21 percent (Spanish type) and 5 to 15 percent (Moroccan and Tunisian type), per EMA. | Dangerous when swallowed; can cause seizures (Poison Control, EFSA via EMA). Not tested separately in the rosemary trials. 26 8 24 | Regulatory |
| Alpha-pinene PubChem 6654 | bicyclic monoterpene | Steam-distilled oil from above-ground parts About 18 to 26 percent (Spanish type) and 9 to 14 percent (Moroccan and Tunisian type), per EMA. | A main component by percentage. No effect data were taken from the sources read. 27 8 | Not assessed |
| Borneol PubChem 64685 | bicyclic monoterpene alcohol | Steam-distilled oil from above-ground parts About 2 to 4.5 percent (Spanish type) and 1.5 to 5 percent (Moroccan and Tunisian type), per EMA. | A minor component by percentage. No effect data were taken from the sources read. 28 8 | Not assessed |
Mechanisms, receptors and pathways
| Target or pathway | Gene or receptor | What was found | Level |
|---|---|---|---|
| Alpha-1 and alpha-2 adrenergic receptors | Adrenergic receptors (alpha-1, alpha-2) | In strips of guinea pig stomach muscle, low concentrations of rosemary oil acted on adrenergic receptors and higher ones relaxed the muscle. Not shown in people. 30 | Laboratory research |
| GABA system and ion channels (seizure link) | GABA neurotransmission; ion channels | A review says the seizure-causing or seizure-preventing effects of essential oils are largely due to GABA-system modulation and altered ion currents; it names 1,8-cineole and camphor among convulsant compounds. The mechanism for rosemary oil itself is not established. 3 | Review of animal and cell work |
| Absorption of 1,8-cineole from breathed-in aroma | n/a | Blood 1,8-cineole after smelling rosemary related to task performance in 20 people; this is a correlation, not proof of cause. 20 | Human observational |
| Smooth muscle relaxation | n/a | EMA reports spasm-relaxing effects of the oil in animal tissue consistent with traditional use. Not shown in people. 8 | Ex vivo |
Absorption, metabolism and elimination
- Absorption
- In 20 volunteers, 1,8-cineole was found in blood after breathing rosemary aroma. In mice, inhaled oil gave detectable blood 1,8-cineole. Skin absorption of the oil was not established in the sources read.
- Distribution
- Not established.
- Metabolism
- Not established for the oil.
- Elimination
- In mice the 1,8-cineole level fell in two phases, with a half-life of about 45 minutes in the second (EMA, quoting an animal study). Not established in people.
- Bioavailability
- Not established. There are no data on transfer into human milk (EMA).
Isolated compounds versus whole extracts
Rosemary essential oil, dried rosemary leaf, rosemary tea and rosemary extracts are different products. EMA treats the oil as a skin medicine and the leaf as a tea and bath product. Results and safety warnings for the leaf or extracts do not carry over to the oil, and the oil itself comes in different chemical types.
Nutritional composition
Rosemary oil is not a nutrient. It is a concentrated aromatic oil and is not meant to be swallowed.
1 mixed findings4 low certainty3 very low certainty2 not enough evidence
What was looked at
The 10 benefits and uses checked for Rosemary Oil, each with how strong the evidence is. Tap one to open it.
- Alertness and sleepiness (smelling the oil)Low certainty
- Memory and thinking speed in healthy adults (smelling the oil)Low certainty
- Memory in older or ill people (smelling the oil)Very low certainty
- Anxiety before surgery, procedures and exams (smelling the oil)Mixed findings
- Sleep quality (smelling the oil)Very low certainty
- Hair loss (rosemary oil on the scalp)Low certainty
- Pain (smelling the oil)Not enough evidence
- Cold hands in systemic sclerosis (Raynaud's phenomenon, oil on the hands)Very low certainty
- Breathing tests (smelling the oil)Low certainty
- Minor muscle and joint aches and leg circulation (traditional skin use)Not enough evidence
Lab markers tracked in the studies
Blood level of 1,8-cineole after smelling rosemary oilSelf-rated sleepiness scoreState anxiety scoreHair count (scalp photographs)Finger skin temperature (infrared camera)
What is Rosemary Oil good for?
The uses people ask about and how strong the evidence is for each. Read the certainty label first: none of the uses is backed by large, independent trials.
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.
Alertness and sleepiness (smelling the oil)
Low certaintyIn one trial of 80 shift-working nurses, one drop of rosemary oil on a mask lowered sleepiness scores compared with a drop of water. It is one trial, people can tell a scent from water, and a small experiment found that what people expect shapes how alert they say they feel.
3 studiesNot covered. This page gives no amounts and no ways of using the oil.
Studies, doses and limits
What the trials found
One randomized field trial of 80 nurses; one double-blind experiment in 33 adults that tested rosemary, lavender and eucalyptus for three minutes each; the 144-person memory trial also asked about mood.
Results
In the nurse trial the sleepiness score fell from 12.15 to 8.3 with rosemary and rose from 11.41 to 13.76 in the water group (P < 0.001); the authors also report better alertness. In the 33-person experiment, changes in alertness differed between oils, and what people expected beforehand predicted how alert they felt for rosemary and lavender. In the 144-person trial the rosemary group felt more alert than the no-scent group afterwards.
Effect sizes as reported
Sleepiness score change: 12.15 to 8.3 (rosemary) against 11.41 to 13.76 (water), P < 0.001.
Why this rating
Only one trial measured sleepiness in a work setting, scores were self-reported, a scent is hard to hide, and a separate experiment shows expectations drive felt alertness.
Form and dose studied
Not covered. This page gives no amounts and no ways of using the oil.
Who was studied
Healthy adults, and shift-working nurses.
Limits
Short exposure; self-rated scales; no long-term follow-up.
Why researchers looked
Rosemary is a well-known 'wake-up' scent, so researchers test it for tiredness and focus.
Traditional use
Rosemary oil has been called a tonic and stimulant since ancient Greece and Rome (EMA assessment report, history section). That is tradition, not proof.
Proposed mechanism Preliminary mechanism
Not established. The papers we read did not test how the smell works in the body.
A proposed mechanism does not show that the effect happens in people.
Smelling the oil is the only use covered here. Do not swallow it, and watch for headache, skin or breathing reactions. See the Safety tab.
Memory and thinking speed in healthy adults (smelling the oil)
Low certaintyIn a 2003 trial of 144 healthy adults, sitting in a room scented with rosemary oil gave better scores on some memory tasks than no scent, but slower memory speed. A small follow-up found that people with more of the oil component 1,8-cineole in their blood did better, which does not prove the scent caused it.
2 studiesNot covered. This page gives no amounts and no ways of using the oil.
Studies, doses and limits
What the trials found
One randomized trial (144 people, three groups: rosemary, lavender, no scent) and one 20-person study with no comparison group that linked blood levels to performance.
Results
Compared with no scent, rosemary improved overall quality of memory and secondary memory but made speed of memory worse. Lavender worsened working memory and reaction times. In the 20-person study, higher blood 1,8-cineole went with better speed and accuracy on thinking tasks, and with lower 'contentment' scores.
Effect sizes as reported
Not given as one number in the abstracts.
Why this rating
One randomized trial from 2003 with a mixed result (better memory quality, slower speed), and a small correlation study that cannot show cause. Neither has been confirmed by a large independent trial in the papers we read.
Form and dose studied
Not covered. This page gives no amounts and no ways of using the oil.
Who was studied
Healthy volunteers (ages not given in the abstracts).
Limits
Short exposure; lab tasks rather than daily life; mixed direction of results.
Why researchers looked
Rosemary has been linked with memory for centuries, so scent studies often test it.
Traditional use
The EMA assessment report says rosemary oil was used in ancient Greece and Rome to strengthen the memory. That is history, not trial evidence.
Proposed mechanism Preliminary mechanism
Not established. The papers we read did not test how the smell works in the body.
A proposed mechanism does not show that the effect happens in people.
Smelling the oil is the only use covered here. Do not swallow it, and watch for headache, skin or breathing reactions. See the Safety tab.
Memory in older or ill people (smelling the oil)
Very low certaintyThree small studies in older or ill people found some memory or thinking scores improved over time. But the better trial found no difference between rosemary and no treatment, and one study used a mix of four oils. This is too thin to say rosemary oil helps memory in illness or ageing.
3 studiesNot covered. This page gives no amounts and no ways of using the oil.
Studies, doses and limits
What the trials found
A randomized trial of 86 dialysis patients (lavender, rosemary, orange and no-scent groups); a randomized trial of 63 people aged 65 or older with diabetes (lavender, rosemary, control, 4 weeks); a controlled trial in 28 older people (17 with Alzheimer's) using a four-oil blend.
Results
Dialysis trial: memory problems fell over time in the rosemary group but no difference was found between the four groups for either kind of memory problem or for taking medicines on time. Diabetes trial: scores for thinking, anxiety and sleep improved from baseline with rosemary and lavender, and the control group's anxiety rose; the abstract does not report a direct comparison between groups. Blend trial: orientation scores and, in the Alzheimer's group, the total score of a dementia test improved; rosemary was used only in the morning with lemon, so its own effect cannot be separated.
Effect sizes as reported
No effect sizes in the abstracts.
Why this rating
Small trials, short, scents cannot be hidden, within-group changes are weaker than between-group comparisons, and the third study mixed four oils.
Form and dose studied
Not covered. This page gives no amounts and no ways of using the oil.
Who was studied
People on dialysis; adults 65+ with diabetes; older adults with and without Alzheimer's.
Limits
No long-term follow-up; no effect on taking medicines on time in the dialysis trial.
Why researchers looked
Researchers wanted to know if the memory link seen in healthy people carries over to people with memory problems.
Proposed mechanism Preliminary mechanism
Not established. The papers we read did not test how the smell works in the body.
A proposed mechanism does not show that the effect happens in people.
Smelling the oil is the only use covered here. Do not swallow it, and watch for headache, skin or breathing reactions. See the Safety tab.
Anxiety before surgery, procedures and exams (smelling the oil)
Mixed findingsResults are mixed. A trial of 236 people before surgery found less anxiety after smelling rosemary, but a trial of 176 people during kidney-stone treatment found no benefit, and a student exam trial using a lavender and rosemary blend found no clear difference either.
4 studiesNot covered. This page gives no amounts and no ways of using the oil.
Studies, doses and limits
What the trials found
Three randomized studies (236, 176 and 45 people) and the 63-person diabetes trial above.
Results
Before general surgery, anxiety fell with rosemary scent, with music and with both, with rosemary showing the largest fall (P = 0.001), compared with an aroma placebo. During kidney-stone shockwave treatment, anxiety after the treatment was higher in the rosemary, music and combined groups than in the water-scent group; the authors conclude none reduced anxiety. In 45 chiropractic students the lavender and rosemary blend did not differ clearly from a distilled-water inhaler (P = 0.10 intention-to-treat, 0.07 per-protocol).
Effect sizes as reported
No effect sizes in the abstracts.
Why this rating
Positive and negative randomized trials sit side by side, the exam trial used a blend and had dropouts, and the set-ups differ.
Form and dose studied
Not covered. This page gives no amounts and no ways of using the oil.
Who was studied
Adults before surgery or a medical procedure; chiropractic students under exam stress.
Limits
Self-rated anxiety; scents are hard to blind; short exposure.
Why researchers looked
Waiting rooms and exams make people anxious, and a scent is a cheap, low-risk idea to test.
Proposed mechanism Preliminary mechanism
Not established. The papers we read did not test how the smell works in the body.
A proposed mechanism does not show that the effect happens in people.
Smelling the oil is the only use covered here. Do not swallow it, and watch for headache, skin or breathing reactions. See the Safety tab.
Sleep quality (smelling the oil)
Very low certaintyOne 4-week trial in 63 older adults with diabetes reported better sleep scores with rosemary scent than at the start. That is the only sleep result we found for rosemary oil, so we cannot say it helps.
1 studiesNot covered. This page gives no amounts and no ways of using the oil.
Studies, doses and limits
What the trials found
One randomized trial of 63 adults aged 65 or older with diabetes (rosemary, lavender, control) over four weeks.
Results
Sleep quality scores at week four were better than baseline in both scent groups. The abstract does not give a direct comparison with the control group for sleep.
Effect sizes as reported
No effect sizes in the abstract.
Why this rating
A single small trial, with within-group changes only reported.
Form and dose studied
Not covered. This page gives no amounts and no ways of using the oil.
Who was studied
Adults 65 and over with diabetes.
Limits
One study; short; self-rated.
Why researchers looked
Aromatherapy is often tried for sleep, though rosemary is better known as a wake-up scent.
Proposed mechanism Preliminary mechanism
Not established. The papers we read did not test how the smell works in the body.
A proposed mechanism does not show that the effect happens in people.
Smelling the oil is the only use covered here. Do not swallow it, and watch for headache, skin or breathing reactions. See the Safety tab.
Hair loss (rosemary oil on the scalp)
Low certaintyOne 6-month trial of 100 people with common pattern hair loss found hair counts rose with rosemary oil about as much as with 2% minoxidil. There was no dummy-treatment group and nothing changed at 3 months. Reviews call this an early result and ask for better trials.
4 studiesNot covered. This page gives no amounts and no ways of using the oil.
Studies, doses and limits
What the trials found
One randomized comparative trial (100 people with androgenetic alopecia, 50 per group) and three later reviews that mention it: a review of 13 investigator-blinded trials of non-prescription products, a network meta-analysis of 24 trials, and a systematic review of 16 herbal trials.
Results
At 3 months neither group had a significant change in hair count. At 6 months both groups had a significant rise in hair count compared with the start, and the two groups did not differ. Scalp itching was higher than at the start in both groups and was more frequent with minoxidil. The 2025 reviews say non-prescription products have limited evidence and need better, larger trials; the network meta-analysis confirms that standard medicines (oral dutasteride, minoxidil, finasteride) work and offers 'guidance' on rosemary oil without numbers in its abstract.
Effect sizes as reported
Hair count rose at 6 months in both groups; no difference between groups (P > 0.05). Effect size not given in the abstract.
Why this rating
One small trial with no placebo group, no stated blinding or oil strength in the abstract, and the comparison drug was minoxidil 2%. Reviewers all ask for larger, better trials.
Form and dose studied
Not covered. This page gives no amounts and no ways of using the oil.
Who was studied
Adults with androgenetic alopecia (common pattern hair loss).
Limits
Six months; photographic hair counts; no placebo group; funding not stated in the abstract. Not a replacement for seeing a doctor about hair loss.
Why researchers looked
Rosemary is a traditional hair tonic, and an early idea was that it might improve blood flow to the scalp.
Traditional use
The EMA assessment report notes rosemary is said to prevent baldness when used as a hair tonic. That is folk use, not proof.
Proposed mechanism Preliminary mechanism
Not established. The papers we read did not test how the smell works in the body.
A proposed mechanism does not show that the effect happens in people.
Skin use can cause itching, rash or allergy. Do not use the oil on broken skin or near the eyes. See the Safety tab.
Pain (smelling the oil)
Not enough evidenceIn a small lab experiment on pain, smelling rosemary oil did not change how sensitive 26 people were to pain. People did say afterwards that it reduced how unpleasant the pain felt, a little, and less than lavender did.
1 studiesNot covered. This page gives no amounts and no ways of using the oil.
Studies, doses and limits
What the trials found
One randomized crossover experiment in 26 healthy adults (13 men, 13 women) comparing lavender oil, rosemary oil and distilled water.
Results
Measured sensitivity to heat, pressure and ischemic pain did not change between conditions. Looking back, people judged pain intensity and unpleasantness lower after lavender and marginally lower after rosemary, compared with water. The authors suggest aromatherapy may change how pain is judged, not the pain itself.
Effect sizes as reported
No effect sizes in the abstract.
Why this rating
Healthy volunteers in a lab, not people with pain conditions, and the only result was a retrospective impression, not a measured change.
Form and dose studied
Not covered. This page gives no amounts and no ways of using the oil.
Who was studied
Healthy men and women.
Limits
One small experiment from 2004; lab pain only.
Why researchers looked
Aromatherapy is often tried for pain, so researchers tested the idea under controlled lab pain.
Proposed mechanism Preliminary mechanism
Not established. The papers we read did not test how the smell works in the body.
A proposed mechanism does not show that the effect happens in people.
Smelling the oil is the only use covered here. See the Safety tab.
Cold hands in systemic sclerosis (Raynaud's phenomenon, oil on the hands)
Very low certaintyIn a 12-person pilot, rosemary oil on the hands made people feel warmer but did not warm the fingers more than olive oil did.
2 studiesNot covered. This page gives no amounts and no ways of using the oil.
Studies, doses and limits
What the trials found
One open-label pilot in 12 people with systemic sclerosis and Raynaud's phenomenon: olive oil on both hands as a control, then rosemary oil three hours later.
Results
Finger skin temperature rose after both oils and the difference between them was not significant. People reported more warmth after rosemary oil but not after olive oil. No adverse effects were observed.
Effect sizes as reported
Not given in the abstract.
Why this rating
Twelve people, open label (no hiding), the control was done first on the same day, and warmth was self-reported.
Form and dose studied
Not covered. This page gives no amounts and no ways of using the oil.
Who was studied
Adults with systemic sclerosis and Raynaud's phenomenon.
Limits
A pilot; funding not stated in the abstract.
Why researchers looked
Rosemary is traditionally said to help circulation, and the EU lists a traditional skin use for minor circulation problems.
Traditional use
EMA accepts rosemary oil skin medicines for minor circulation problems in the legs on traditional use alone.
Proposed mechanism Preliminary mechanism
Not established. The papers we read did not test how the smell works in the body.
A proposed mechanism does not show that the effect happens in people.
Skin use can cause itching, rash or allergy. Do not use the oil on broken skin or near the eyes. See the Safety tab.
Breathing tests (smelling the oil)
Low certaintyIn 106 healthy people, breathing in a mist of rosemary oil for 15 minutes did not change lung function tests.
2 studiesNot covered. This page gives no amounts and no ways of using the oil.
Studies, doses and limits
What the trials found
One randomized experiment in 106 healthy people given nebulized peppermint, eucalyptus or rosemary oil for 15 minutes, or no treatment.
Effect sizes as reported
No change in measured lung function.
Why this rating
Healthy people only; it says nothing about asthma, COPD or children; a single 15-minute exposure.
Form and dose studied
Not covered. This page gives no amounts and no ways of using the oil.
Who was studied
Healthy adults.
Limits
Does not test people with lung disease or longer exposure.
Why researchers looked
Aromatherapy oils are often marketed for easier breathing, so this trial checked the lung function directly.
Proposed mechanism Preliminary mechanism
Not established.
A proposed mechanism does not show that the effect happens in people.
Hypersensitivity (asthma-type reactions) is listed for the oil by EMA; the frequency is not known. People with asthma should ask a clinician. See the Safety tab.
Minor muscle and joint aches and leg circulation (traditional skin use)
Not enough evidenceThe EU accepts rosemary oil skin medicines for minor muscle and joint aches and minor leg circulation problems, but only because of long traditional use. The assessment found no clinical studies for these uses.
2 studiesNot covered. This page gives no amounts and no ways of using the oil.
Studies, doses and limits
What the trials found
No clinical trials were found by the EU committee for these uses.
Results
Not tested in trials. The committee also says laboratory studies on isolated parts of animals and tissue show a relaxing effect on smooth muscle that fits the traditional use.
Why this rating
Tradition only. Licensed rosemary oil medicines are skin creams for adults, not bottled oil.
Form and dose studied
Not covered. This page gives no amounts and no ways of using the oil.
Who was studied
Adults only (EMA: not for under 18s).
Limits
Marketed products and long use do not show that it works.
Why researchers looked
Rosemary oil has long been used in baths, rubs and creams for aches.
Traditional use
The EU herbal committee accepts these uses as traditional (at least 30 years of use, 15 in the EU), not as proven by trials.
Proposed mechanism Preliminary mechanism
Laboratory work on animal tissue shows muscle-relaxing activity (EMA assessment report). Not shown in people.
A proposed mechanism does not show that the effect happens in people.
Skin use can cause itching, rash or allergy. Do not use the oil on broken skin or near the eyes. See the Safety tab.
Connections to the rest of health
How Rosemary Oil 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
A. Wellness goals
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Mental Clarity | Low certainty | Alertness and sleepiness (smelling the oil): In one trial of 80 shift-working nurses, one drop of rosemary oil on a mask lowered sleepiness scores compared with a drop of water. It is one trial, people can tell a scent from water, and a small experiment found that what people expect shapes how alert they say they feel. Memory and thinking speed in healthy adults (smelling the oil): In a 2003 trial of 144 healthy adults, sitting in a room scented with rosemary oil gave better scores on some memory tasks than no scent, but slower memory speed. A small follow-up found that people with more of the oil component 1,8-cineole in their blood did better, which does not prove the scent caused it. | 21 16 19 20 | |
| Better Focus | Low certainty | Alertness and sleepiness (smelling the oil): In one trial of 80 shift-working nurses, one drop of rosemary oil on a mask lowered sleepiness scores compared with a drop of water. It is one trial, people can tell a scent from water, and a small experiment found that what people expect shapes how alert they say they feel. | 21 16 19 | |
| Memory Support | Low certainty | Memory and thinking speed in healthy adults (smelling the oil): In a 2003 trial of 144 healthy adults, sitting in a room scented with rosemary oil gave better scores on some memory tasks than no scent, but slower memory speed. A small follow-up found that people with more of the oil component 1,8-cineole in their blood did better, which does not prove the scent caused it. Memory in older or ill people (smelling the oil): Three small studies in older or ill people found some memory or thinking scores improved over time. But the better trial found no difference between rosemary and no treatment, and one study used a mix of four oils. This is too thin to say rosemary oil helps memory in illness or ageing. | 19 20 6 5 15 | |
| Brain Health | Low certainty | Memory and thinking speed in healthy adults (smelling the oil): In a 2003 trial of 144 healthy adults, sitting in a room scented with rosemary oil gave better scores on some memory tasks than no scent, but slower memory speed. A small follow-up found that people with more of the oil component 1,8-cineole in their blood did better, which does not prove the scent caused it. Memory in older or ill people (smelling the oil): Three small studies in older or ill people found some memory or thinking scores improved over time. But the better trial found no difference between rosemary and no treatment, and one study used a mix of four oils. This is too thin to say rosemary oil helps memory in illness or ageing. | 19 20 6 5 15 | |
| Healthy Aging | Very low certainty | Memory in older or ill people (smelling the oil): Three small studies in older or ill people found some memory or thinking scores improved over time. But the better trial found no difference between rosemary and no treatment, and one study used a mix of four oils. This is too thin to say rosemary oil helps memory in illness or ageing. | 6 5 15 | |
| Anxiety Support | Mixed findings | Anxiety before surgery, procedures and exams (smelling the oil): Results are mixed. A trial of 236 people before surgery found less anxiety after smelling rosemary, but a trial of 176 people during kidney-stone treatment found no benefit, and a student exam trial using a lavender and rosemary blend found no clear difference either. | 31 29 9 5 | |
| Calm Relaxation | Mixed findings | Anxiety before surgery, procedures and exams (smelling the oil): Results are mixed. A trial of 236 people before surgery found less anxiety after smelling rosemary, but a trial of 176 people during kidney-stone treatment found no benefit, and a student exam trial using a lavender and rosemary blend found no clear difference either. | 31 29 9 5 | |
| Stress Reduction | Mixed findings | Anxiety before surgery, procedures and exams (smelling the oil): Results are mixed. A trial of 236 people before surgery found less anxiety after smelling rosemary, but a trial of 176 people during kidney-stone treatment found no benefit, and a student exam trial using a lavender and rosemary blend found no clear difference either. | 31 29 9 5 | |
| Better Sleep | Very low certainty | Sleep quality (smelling the oil): One 4-week trial in 63 older adults with diabetes reported better sleep scores with rosemary scent than at the start. That is the only sleep result we found for rosemary oil, so we cannot say it helps. | 5 | |
| Sleep Quality | Very low certainty | Sleep quality (smelling the oil): One 4-week trial in 63 older adults with diabetes reported better sleep scores with rosemary scent than at the start. That is the only sleep result we found for rosemary oil, so we cannot say it helps. | 5 | |
| Hair Support | Low certainty | Hair loss (rosemary oil on the scalp): One 6-month trial of 100 people with common pattern hair loss found hair counts rose with rosemary oil about as much as with 2% minoxidil. There was no dummy-treatment group and nothing changed at 3 months. Reviews call this an early result and ask for better trials. | 23 13 14 2 | |
| Mobility Support | Not enough evidence | Pain (smelling the oil): In a small lab experiment on pain, smelling rosemary oil did not change how sensitive 26 people were to pain. People did say afterwards that it reduced how unpleasant the pain felt, a little, and less than lavender did. | 11 | |
| Healthy Circulation | Very low certainty | Cold hands in systemic sclerosis (Raynaud's phenomenon, oil on the hands): In a 12-person pilot, rosemary oil on the hands made people feel warmer but did not warm the fingers more than olive oil did. | 32 7 | |
| Breathing Support | Low certainty | Breathing tests (smelling the oil): In 106 healthy people, breathing in a mist of rosemary oil for 15 minutes did not change lung function tests. | 17 7 | |
| Joint Support | Traditional use | Not enough evidence | Minor muscle and joint aches and leg circulation (traditional skin use): The EU accepts rosemary oil skin medicines for minor muscle and joint aches and minor leg circulation problems, but only because of long traditional use. The assessment found no clinical studies for these uses. | 7 8 |
| Muscle Recovery | Traditional use | Not enough evidence | Minor muscle and joint aches and leg circulation (traditional skin use): The EU accepts rosemary oil skin medicines for minor muscle and joint aches and minor leg circulation problems, but only because of long traditional use. The assessment found no clinical studies for these uses. | 7 8 |
| Healthy Circulation | Traditional use | Not enough evidence | Minor muscle and joint aches and leg circulation (traditional skin use): The EU accepts rosemary oil skin medicines for minor muscle and joint aches and minor leg circulation problems, but only because of long traditional use. The assessment found no clinical studies for these uses. | 7 8 |
B. Body systems
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Brain Focus | Biological association | Low certainty | Studied for: Alertness and sleepiness (smelling the oil) Studied for: Memory and thinking speed in healthy adults (smelling the oil) | 21 16 19 20 6 5 15 |
| Nervous System | Biological association | Low certainty | Studied for: Alertness and sleepiness (smelling the oil) Studied for: Memory and thinking speed in healthy adults (smelling the oil) | 21 16 19 20 6 5 15 31 29 9 11 |
| Stress Mood | Biological association | Mixed findings | Studied for: Anxiety before surgery, procedures and exams (smelling the oil) | 31 29 9 5 |
| Sleep Recovery | Biological association | Very low certainty | Studied for: Sleep quality (smelling the oil) | 5 |
| Skin Hair Beauty | Biological association | Low certainty | Studied for: Hair loss (rosemary oil on the scalp) | 23 13 14 2 |
| Pain Inflammation | Biological association | Not enough evidence | Studied for: Pain (smelling the oil) | 11 |
| Heart Circulation | Biological association | Very low certainty | Studied for: Cold hands in systemic sclerosis (Raynaud's phenomenon, oil on the hands) Studied for: Minor muscle and joint aches and leg circulation (traditional skin use) | 32 7 8 |
| Respiratory Health | Biological association | Low certainty | Studied for: Breathing tests (smelling the oil) | 17 7 |
| Bones Joints Muscles | Biological association | Not enough evidence | Studied for: Minor muscle and joint aches and leg circulation (traditional skin use) | 7 8 |
E. Health conditions
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Contact dermatitis | Adverse effect or risk | Documented risk | Listed by EMA for the oil with unknown frequency; case reports mostly involve the plant or extracts. Preparation or compound: Rosemary oil and rosemary extracts |
7 18 22 |
| Seizures | Not enough evidence | Named in a review and a case-report paper among oils that can trigger seizures when taken in; not shown for smelling or skin use. Preparation or compound: Swallowed rosemary oil (camphor, 1,8-cineole) |
3 4 8 | |
| Asthma | Adverse effect or risk | Not enough evidence | EMA lists asthma-type hypersensitivity with unknown frequency; no change in lung function tests in healthy people. Preparation or compound: Rosemary oil |
7 17 |
| Androgenetic alopecia | Preliminary mixed | One 6-month randomized trial: hair count rose, similar to minoxidil 2%; reviews call evidence limited. Preparation or compound: Rosemary oil on the scalp |
23 13 |
I. Biomarkers
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Blood level of 1,8-cineole after smelling rosemary oil | Biological association | Very low certainty | Measured in trials: increase. A lab change is not the same as a health benefit. | 20 |
| Self-rated sleepiness score | Biological association | Low certainty | Measured in trials: decrease. A lab change is not the same as a health benefit. | 21 |
| State anxiety score | Biological association | Mixed findings | Measured in trials: decrease. A lab change is not the same as a health benefit. | 31 29 9 |
| Hair count (scalp photographs) | Biological association | Low certainty | Measured in trials: increase. A lab change is not the same as a health benefit. | 23 |
| Finger skin temperature (infrared camera) | Biological association | Very low certainty | Measured in trials: increase. A lab change is not the same as a health benefit. | 32 |
J. Genes, receptors and enzymes
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Alpha-1 and alpha-2 adrenergic receptors | Preliminary mechanism | In vitro | Lab activity of rosemary oil on guinea pig stomach muscle. | 30 |
K. Biological pathways
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| GABA neurotransmission | Preliminary mechanism | Review of animal and cell work | Proposed route for convulsant effects of some essential oils (review); not shown for rosemary oil specifically. | 3 |
L. Active compounds
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| 1,8-Cineole (eucalyptol) | Biological association | Human observational | Absorbed into the blood when the aroma is breathed in (human study). Named with camphor as a seizure-linked compound when oils are swallowed (review). Preparation or compound: Steam-distilled oil from above-ground parts |
25 8 20 3 |
| Camphor | Biological association | Regulatory | Dangerous when swallowed; can cause seizures (Poison Control, EFSA via EMA). Not tested separately in the rosemary trials. Preparation or compound: Steam-distilled oil from above-ground parts |
26 8 24 |
| Alpha-pinene | Biological association | Not assessed | A main component by percentage. No effect data were taken from the sources read. Preparation or compound: Steam-distilled oil from above-ground parts |
27 8 |
| Borneol | Biological association | Not assessed | A minor component by percentage. No effect data were taken from the sources read. Preparation or compound: Steam-distilled oil from above-ground parts |
28 8 |
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 the research found for 10 outcomes
Each outcome below is one thing researchers measured. Certainty is how far the evidence can be trusted, not how well it works. The full studies are on the next tab.
The evidence
The research centre for Rosemary Oil. Every record here was checked against PubMed or the publisher's page; we never list a study we have not verified.
Evidence by outcome
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 read the abstracts of 23 PubMed papers and the EMA assessment report (full text) and the EMA, Poison Control and ASPCA pages, checked the plant name in GBIF and the compounds in PubChem. We did not find or read a LiverTox, LactMed or FDA statement.
Study library: every study we checked 32
| Study | Design | People | Product, dose, length | Result |
|---|---|---|---|---|
| ASPCA Animal Poison Control Non-toxic plants: Rosemary ASPCA website · Source |
Authoritative guidance dog, cat, horse (listing) |
Dogs, cats, horses | Rosemary plant (Rosmarinus officinalis) plant |
Lists the rosemary plant as non-toxic to dogs, cats and horses. This is a plant listing; it does not cover the concentrated essential oil. Methods, limits and fundingOutcomes: Pet toxicity listing Limitations: Plant only; no oil-specific pet guidance was found in the sources read. Read: full-text |
| Allam 2025 Pathophysiology, conventional treatments, and evidence-based herbal remedies of hair loss with a systematic review of controlled clinical trials Naunyn Schmiedebergs Arch Pharmacol · PMID 40536553 · DOI |
Systematic review of randomized controlled trials |
16 randomized trials of herbal remedies for hair loss | Herbal remedies including rosemary various Not reported here |
Describes rosemary, green tea, ginseng, aloe vera, olive and saw palmetto as promising for hair, but notes design limits and varied outcomes, and calls for standardized research. Methods, limits and fundingOutcomes: Hair density, shedding, satisfaction Limitations: Reviews many herbs together; abstract does not give rosemary-specific numbers. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Bahr 2019 The Effects of Various Essential Oils on Epilepsy and Acute Seizure: A Systematic Review Evid Based Complement Alternat Med · PMID 31239862 · DOI |
Systematic review human, animal, cell |
Human case reports, animal and cell studies on essential oils and seizures | Many essential oils, including rosemary (internal use) essential oils Not reported here |
Says internal use of oils including sage, hyssop, rosemary, camphor, pennyroyal, eucalyptus, cedar, thuja and fennel can cause epileptic seizures because of thujone, 1,8-cineole, camphor or pinocamphone; proposes GABA-system and ion-channel effects as likely mechanisms. Methods, limits and fundingOutcomes: Convulsant or anticonvulsant effects Limitations: Mixes human cases, animal and cell studies; about internal use, not smelling or skin use; the abstract does not separate rosemary from the others. Funding and conflicts: Authors list an affiliation with an essential oil company (dōTERRA International). Read: abstract |
| Burkhard 1999 Plant-induced seizures: reappearance of an old problem J Neurol · PMID 10460442 · DOI |
Case reports and literature survey |
3 Three healthy patients (two adults, one child) with seizures |
Several essential oils absorbed for therapeutic purposes (the abstract does not say which oil caused each case) essential oils Not reported here |
All three had a generalized seizure linked to using several essential oils; no other cause was found; outcomes were good in the two adults and less favourable in the child. A literature survey in the paper names oils of 11 plants, rosemary among them, as powerful convulsants because of ketones such as camphor and cineole. Methods, limits and fundingOutcomes: Seizure, outcome Limitations: The cases involved several oils, so a rosemary-only case is not shown; 1999 paper. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Can 2024 The effect of lavender and rosemary aromatherapy application on cognitive functions, anxiety, and sleep quality in the elderly with diabetes Explore (NY) · PMID 39047346 · DOI |
Randomized controlled trial |
63 63 adults aged 65 and over with diabetes |
Rosemary or lavender aromatherapy (inhaled) essential oil Not reported here four weeks · vs control group |
Scores for thinking, anxiety and sleep at week four were better than baseline in both scent groups. In the control group state anxiety was higher at weeks two and four than at the start. Methods, limits and fundingOutcomes: Blessed Orientation Concentration Test, State-Trait Anxiety Scale, Pittsburgh Sleep Quality Scale Limitations: Small; one population; reports changes from baseline; the abstract gives no direct between-group comparison. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Dehghan 2022 The effects of lavender, rosemary and orange essential oils on memory problems and medication adherence among patients undergoing hemodialysis: A parallel randomized controlled trial Explore (NY) · PMID 34736874 · DOI |
Parallel randomized controlled trial |
86 86 people on chronic hemodialysis in Iran |
Rosemary essential oil on gauze (compared with lavender, orange and control) essential oil Not reported here three times a week for one month · vs no-scent control |
Retrospective memory problems fell within the lavender and rosemary groups over time, but no difference between the four groups was found for either kind of memory problem or for medication adherence. Methods, limits and fundingOutcomes: Retrospective and prospective memory problems, medication adherence Limitations: Within-group changes only; no effect on adherence; one setting. Trial registered (IRCT20190428043410N1). Funding and conflicts: Not stated in the abstract. Read: abstract |
| EMA Committee on Herbal Medicinal Products (HMPC) 2024 Rosmarini aetheroleum (rosemary oil): herbal medicinal product, EU herbal monograph and public summary EMA herbal medicines page · Source |
Authoritative guidance |
Adults; skin products only | Rosemary essential oil in semi-solid skin medicines essential oil of the above-ground parts |
Traditional use (long-standing use, not clinical trials) of rosemary oil skin products for minor muscle and joint pain and minor circulation problems in the legs. Not for under 18s, in pregnancy or breastfeeding, with rosemary allergy, or with known heart or kidney disease; not near the eyes or mucous membranes. No interactions described in the literature at the time. Side effects: contact dermatitis or asthma-type breathing difficulty, frequency not known. Methods, limits and fundingOutcomes: Traditional use, who should not use it, interactions, side effects Limitations: Covers licensed skin medicines only; it excludes foods, supplements, cosmetics and diffusers. Read: full-text |
| EMA Committee on Herbal Medicinal Products (HMPC) 2024 Assessment report on Rosmarinus officinalis L., aetheroleum and Rosmarinus officinalis L., folium (Final, Revision 1), EMA/HMPC/681037/2021 EMA/HMPC/681037/2021 (29 May 2024) · Source |
Authoritative guidance |
Assessment of rosemary leaf and rosemary essential oil | Rosemary essential oil and leaf essential oil (steam distillation of aerial parts) and leaf |
Gives the oil composition ranges for two types (Spanish type and Moroccan/Tunisian type), says no clinical studies exist for the traditional-use indications, no clinical trial safety data, serious poisoning by rosemary or its oil is not reported, rat swallowed-oil LD50 5.5 g/kg, camphor poisoning facts from EFSA, asthma and contact dermatitis listed with frequency not known, and no human data supporting seizures from ingestion of rosemary extracts. Recommends the oil for skin use only, not under 18, and not in pregnancy or breastfeeding for lack of data. Methods, limits and fundingOutcomes: History, composition, toxicology, clinical safety, conclusions Limitations: A secondary summary; most safety data are old, unpublished or from animals and isolated compounds. Several statements concern the leaf or extracts, not the oil. Read: full-text |
| Enwright 2023 Effect of lavender and rosemary aromatherapy on test anxiety in chiropractic students J Chiropr Educ · PMID 36306254 · DOI |
Randomized crossover trial |
45 45 first-trimester chiropractic students during final exams (38 finished per protocol) |
Nasal inhaler with a lavender and rosemary blend essential oil blend Not reported here two exam days, 2-day wash-out · vs distilled water inhaler |
No statistically significant difference in change in anxiety between the blend and water (ITT p = 0.10; per-protocol p = 0.07). p = 0.10 (ITT), p = 0.07 (per protocol) Methods, limits and fundingOutcomes: Test anxiety survey scores Limitations: A blend, so rosemary cannot be isolated; dropouts; one student group. Funding and conflicts: Not stated in the abstract. Read: abstract |
| GBIF Secretariat 2026 GBIF Backbone Taxonomy: Salvia rosmarinus Spenn., species key 10902460 (GBIF match API) GBIF species match API · Source |
Registry or database n/a |
n/a | n/a |
Accepted species name Salvia rosmarinus Spenn., family Lamiaceae, order Lamiales, status ACCEPTED, match type EXACT. The name Rosmarinus officinalis L. (key 2926634) is listed as a synonym pointing to the accepted key 10902460. Methods, limits and fundingOutcomes: Accepted name and family Read: full-text |
| Gedney 2004 Sensory and affective pain discrimination after inhalation of essential oils Psychosom Med · PMID 15272109 · DOI |
Randomized crossover experiment |
26 26 healthy adults (13 men, 13 women) |
Inhaled lavender oil, rosemary oil, or distilled water essential oil Not reported here single sessions · vs distilled water |
No change in measured pain sensitivity between conditions. Retrospectively, pain intensity and unpleasantness were judged lower after lavender and marginally lower after rosemary compared with water. Methods, limits and fundingOutcomes: Contact heat, pressure and ischemic pain ratings; pain intensity and unpleasantness Limitations: Healthy volunteers, lab pain, small. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Ghasemzadeh Rahbardar 2025 Toxicity and safety of rosemary (Rosmarinus officinalis): a comprehensive review Naunyn Schmiedebergs Arch Pharmacol · PMID 39096378 · DOI |
Narrative review of toxicity human, animal, cell |
Animal, cell and some human reports on rosemary preparations | Rosemary (extracts and oil) various Not reported here |
Reports allergic reactions and dermatitis in some people; reports liver and kidney changes, lower sperm and hormone measures and fetal anomalies in studies, mostly high or chronic doses; urges caution with chronic and high doses and with drug interactions. Methods, limits and fundingOutcomes: Organ, reproductive and genetic toxicity; allergy Limitations: Mixes extracts, oils, animal and cell data; the abstract gives no oil-only findings. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Gupta 2025 Do Non-Prescription Products Help in Managing Androgenic Alopecia? Skin Appendage Disord · PMID 40475103 · DOI |
Review of investigator blinded controlled trials |
13 trials of non-prescription products for androgenetic alopecia (rosemary oil is one of eight products) | Procyanidin, cetirizine, caffeine, rice bran, pumpkin seed oil, rosemary oil, saw palmetto and watercress various Not reported here |
Considerable improvement in one or more hair measures with the products reviewed; minimal adverse events; the authors say evidence is limited and more robust trials with larger numbers and long-term safety data are needed. Methods, limits and fundingOutcomes: Hair density, terminal hair density, hair diameter Limitations: Reviews very different products; rosemary oil is only one of them. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Gupta 2025 Relative Efficacy of Conventional Monotherapies and Select Nonconventional, Over-the-Counter Products for Male Androgenetic Alopecia: A Network Meta-Analysis Study J Cosmet Dermatol · PMID 41051009 · DOI |
Network meta analysis |
24 trials in male androgenetic alopecia (eight conventional and seven non-conventional treatments) | Conventional drugs and select products including topical rosemary oil various Not reported here 24 weeks (hair density) |
Confirms the efficacy of oral dutasteride, minoxidil and finasteride; gives guidance on topical melatonin and rosemary oil relative to them. Rosemary oil numbers are not in the abstract. Methods, limits and fundingOutcomes: Change in total hair density at 24 weeks Limitations: Abstract gives no rosemary number; male patients only. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Jimbo 2009 Effect of aromatherapy on patients with Alzheimer's disease Psychogeriatrics · PMID 20377818 · DOI |
Controlled clinical trial, before and after |
28 28 older people, 17 with Alzheimer's disease |
Four-oil aromatherapy: rosemary and lemon oils in the morning, lavender and orange in the evening essential oil blend Not reported here 28 days with 28-day control and wash-out periods · vs own control period |
Personal orientation scores improved after the aromatherapy period on two scales, and the total TDAS score improved in the Alzheimer's group. Routine lab tests did not change. Methods, limits and fundingOutcomes: Gottfries-Brane-Steen scale, FAST, revised Hasegawa scale, Touch Panel-type Dementia Assessment Scale Limitations: A four-oil blend, so rosemary cannot be separated; no randomization; no placebo scent; very small sample. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Köteles 2014 Role of expectations and pleasantness of essential oils in their acute effects Acta Physiol Hung · PMID 25183507 · DOI |
Double blind within subject experiment |
33 33 volunteers (mean age 37.7; 15.2% men) |
Rosemary, lavender and eucalyptus essential oils, each inhaled for three minutes essential oil Not reported here three minutes per oil · vs the other oils (no no-scent group) |
Alertness changes differed by group; expectations predicted alertness changes for rosemary and lavender but not blood pressure or heart rate; pleasantness had no effect. Methods, limits and fundingOutcomes: Perceived alertness, heart rate, blood pressure, heart rate variability, expectations Limitations: Small; tests expectation as much as the oil; no no-scent group. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Köteles 2018 Inhaled peppermint, rosemary and eucalyptus essential oils do not change spirometry in healthy individuals Physiol Behav · PMID 29913229 · DOI |
Randomized experiment |
106 106 healthy adults |
Nebulized rosemary, peppermint or eucalyptus essential oil essential oil Not reported here 15 minutes · vs no treatment |
None of the oils changed the lung function measures; expectations predicted perceived change but not measured change. No change in spirometry Methods, limits and fundingOutcomes: Forced vital capacity, peak expiratory flow, FEV1/FVC ratio, expectations Limitations: Healthy people, single exposure. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Miroddi 2014 Rosmarinus officinalis L. as cause of contact dermatitis Allergol Immunopathol (Madr) · PMID 23827646 · DOI |
Review of case reports |
Published case reports of contact dermatitis from rosemary | Rosemary as raw material or herbal preparation (extracts) plant material and extracts Not reported here |
Rosemary extracts and raw material can cause allergic contact dermatitis; two cases involved cross-reaction with thyme; carnosol is a suspected cause; the authors think it may be more common than supposed because it is misdiagnosed. Methods, limits and fundingOutcomes: Allergic contact dermatitis Limitations: Covers plant material and extracts, not specifically the essential oil. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Moss 2003 Aromas of rosemary and lavender essential oils differentially affect cognition and mood in healthy adults Int J Neurosci · PMID 12690999 · DOI |
Randomized trial, three groups |
144 144 healthy volunteers tested in a cubicle with a scent or no scent |
Rosemary essential oil aroma in a cubicle (lavender oil and no-scent comparison) essential oil Not reported here single session during a computerized test battery · vs no scent (lavender oil as a second comparison) |
Rosemary improved overall quality of memory and secondary memory but made speed of memory worse than no scent. Lavender worsened working memory and slowed reaction times. After testing, the control and lavender groups were less alert than the rosemary group. Methods, limits and fundingOutcomes: Six cognitive factors from the CDR battery; mood scales Limitations: Healthy volunteers; one session; lab tasks; 2003 trial. Participants were not told the true aim until the end, which reduces expectation effects. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Moss 2012 Plasma 1,8-cineole correlates with cognitive performance following exposure to rosemary essential oil aroma Ther Adv Psychopharmacol · PMID 23983963 · DOI |
Single group correlation study |
20 20 healthy volunteers |
Rosemary essential oil aroma diffused in a cubicle essential oil Not reported here one session |
Higher blood 1,8-cineole went with better speed and accuracy. Change in contentment correlated negatively with cineole level. Pearson correlations (no effect size in the abstract) Methods, limits and fundingOutcomes: Serum 1,8-cineole, serial subtraction and visual information tasks, mood Limitations: No comparison group and a very small sample, so it cannot show cause. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Nasiri 2021 The effect of rosemary essential oil inhalation on sleepiness and alertness of shift-working nurses: A randomized, controlled field trial Complement Ther Clin Pract · PMID 33550193 · DOI |
Randomized controlled field trial |
80 80 shift-working nurses |
Rosemary essential oil, one drop on a mask essential oil Not reported here single use during a shift · vs one drop of distilled water on a mask |
Sleepiness fell from 12.15 to 8.3 with rosemary and rose from 11.41 to 13.76 with water (P < 0.001); alertness scores also differed (P < 0.001). Between-group P < 0.001 (no confidence interval in the abstract) Methods, limits and fundingOutcomes: Karolinska Sleepiness and Epworth Sleepiness scores Limitations: One short exposure; self-rated; a scent is hard to hide from the person using it. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Omeragic 2022 Application of direct peptide reactivity assay for assessing the skin sensitization potential of essential oils Sci Rep · PMID 35523830 · DOI |
Laboratory test (direct peptide reactivity assay) laboratory (in chemico) |
Six commercial essential oils from the mint family (test-tube test) | Rosemary essential oil (with lavender, lemon balm, wild mint, thyme and sage oils) essential oil Not reported here 24-hour incubation · vs peptide-only controls |
Rosemary oil showed low reactivity (12.79% cysteine depletion) but the test classified it, with all oils except wild mint, as positive for skin sensitisation potential. Methods, limits and fundingOutcomes: Cysteine and lysine peptide depletion (predicts skin sensitisation) Limitations: A test-tube prediction, not a human patch test. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Panahi 2015 Rosemary oil vs minoxidil 2% for the treatment of androgenetic alopecia: a randomized comparative trial Skinmed · PMID 25842469 |
Randomized comparative trial |
100 100 people with androgenetic alopecia |
Rosemary oil applied to the scalp (compared with minoxidil 2%) essential oil Not reported here 6 months · vs minoxidil 2% (no placebo group) |
No significant change in hair count at 3 months in either group; both groups rose significantly at 6 months compared with baseline; no significant difference between groups. Scalp itching was higher than baseline in both groups and more frequent with minoxidil. Between-group difference not significant (P > .05); no effect size in the abstract Methods, limits and fundingOutcomes: Hair count by standardized microphotography; dry, greasy hair; dandruff; scalp itching Limitations: No placebo group, oil strength and blinding not stated in the abstract, a single study from 2015. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Poison Control (National Capital Poison Center); Soloway Essential oils: Poisonous when misused Poison Control website · Source |
Authoritative guidance |
General public | Essential oils in general (rosemary oil is not named) oils |
Misuse of essential oils can cause serious poisoning; many cause rashes on the skin; some are poisonous if swallowed or absorbed; children may be more susceptible; choking on an oil can cause pneumonia; keep oils locked away from children and pets; stop and wash off if a rash starts. Camphor (a rosemary oil component) is dangerous if swallowed and can cause seizures within minutes. Poison centre: 1-800-222-1222 in the US. Methods, limits and fundingOutcomes: General essential-oil safety Limitations: General page: it does not name rosemary oil and gives no rosemary-specific case. Read: full-text |
| PubChem 2026 PubChem compound record: 1,8-cineole (CID 2758) PubChem PUG REST · Source |
Registry or database n/a |
n/a | n/a |
Compound 1,8-cineole, CID 2758, formula C10H18O (name lookup via the PubChem API, read 2026-10-25). Methods, limits and fundingOutcomes: Compound identity Limitations: Identity only; no activity data were taken from this record. Read: full-text |
| PubChem 2026 PubChem compound record: camphor (CID 2537) PubChem PUG REST · Source |
Registry or database n/a |
n/a | n/a |
Compound camphor, CID 2537, formula C10H16O (name lookup via the PubChem API, read 2026-10-25). Methods, limits and fundingOutcomes: Compound identity Limitations: Identity only; no activity data were taken from this record. Read: full-text |
| PubChem 2026 PubChem compound record: alpha-pinene (CID 6654) PubChem PUG REST · Source |
Registry or database n/a |
n/a | n/a |
Compound alpha-pinene, CID 6654, formula C10H16 (name lookup via the PubChem API, read 2026-10-25). Methods, limits and fundingOutcomes: Compound identity Limitations: Identity only; no activity data were taken from this record. Read: full-text |
| PubChem 2026 PubChem compound record: borneol (CID 64685) PubChem PUG REST · Source |
Registry or database n/a |
n/a | n/a |
Compound borneol, CID 64685, formula C10H18O (name lookup via the PubChem API, read 2026-10-25). Methods, limits and fundingOutcomes: Compound identity Limitations: Identity only; no activity data were taken from this record. Read: full-text |
| Rohi Ganji 2022 The Effect of Inhalation Aromatherapy and Music Therapy on Anxiety in Patients Undergoing Shockwave Lithotripsy: A Randomized Controlled Clinical Trial Evid Based Complement Alternat Med · PMID 35815287 · DOI |
Randomized controlled clinical trial |
176 176 patients having shockwave lithotripsy for kidney stones |
Rosemary essential oil (compared with music, both, and aromatic water) essential oil Not reported here during the procedure · vs aromatic distilled water |
Groups did not differ before the intervention. Afterwards anxiety was higher in the music, aroma and combined groups than in the control group; the authors conclude none lowered anxiety. Methods, limits and fundingOutcomes: State-Trait Anxiety Inventory Limitations: A negative trial. Anxiety rose in the treated groups, which the abstract does not explain. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Sagorchev 2010 Investigations into the specific effects of rosemary oil at the receptor level Phytomedicine · PMID 20034774 · DOI |
Laboratory study (isolated guinea pig stomach muscle) animal (in vitro) |
Circular smooth-muscle strips from guinea pig stomach | Rosemary oil essential oil Not reported here |
Rosemary oil acted like an agonist on alpha-1 and alpha-2 adrenergic receptors at low concentrations and had a muscle-relaxing effect at higher ones. The authors suggest this might improve local blood flow and ease pain, which was not tested in people. Methods, limits and fundingOutcomes: Contractile activity of muscle strips Limitations: Animal tissue in a dish; far from use on or around people. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Sayadi Mank-Halati 2024 Comparing the effects of rosemary aromatherapy and music therapy on anxiety levels in patients undergoing general surgery: A randomized controlled clinical trial Explore (NY) · PMID 38242798 · DOI |
Randomized controlled clinical trial |
236 236 patients scheduled for general surgery |
Rosemary essential oil inhaled (compared with music, both, and an aromatic placebo) essential oil Not reported here 30 minutes starting one hour before surgery · vs aromatic placebo (59 per group) |
Anxiety fell with rosemary scent (P = 0.001), music (P < 0.001) and both (P = 0.001); rosemary scent had the largest effect and the combination the smallest. P values only in the abstract Methods, limits and fundingOutcomes: Spielberger State Anxiety Inventory Limitations: Self-rated anxiety; one site; the abstract gives no effect sizes. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Vagedes 2022 Topical Rosmarinus officinalis L. in Systemic Sclerosis-Related Raynaud's Phenomenon: An Open-Label Pilot Study Complement Med Res · PMID 35139518 · DOI |
Open label pilot |
12 12 people with systemic sclerosis and Raynaud's phenomenon |
Rosemary essential oil on the hands (olive oil on the hands as control) essential oil Not reported here a single session · vs olive oil, applied three hours earlier |
Skin temperature rose after both olive oil and rosemary oil with no significant difference; warmth perception rose after rosemary oil but not olive oil. No adverse effects were observed. Methods, limits and fundingOutcomes: Skin temperature (infrared thermography), warmth perception Limitations: Open label, 12 people, single session, control not randomized in order. Funding and conflicts: Not stated in the abstract. Read: abstract |
What we do not know yet
- What the evidence supports: rosemary oil is low for alertness, hair loss and healthy-adult memory; mixed for anxiety; very low or insufficient for everything else.
- No large, independent trials exist for any use.
- No placebo-controlled hair trial of the oil was found.
- No oil-specific pregnancy, pet or epilepsy study was found.
- No LiverTox, LactMed, NCCIH or FDA statement on the oil was read.
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 is added.
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 5
Blood level of 1,8-cineole after smelling rosemary oil
Increase in trials
1,8-cineole is one of the main compounds in rosemary oil. This measure shows how much of it reached the blood after breathing the scent.
Very low certaintyResults and what it means
Why it was measured
To see whether absorbed compounds, not just the smell, relate to thinking scores.
Statistical vs. clinical meaning
An exposure marker, not a health outcome. It shows the compound is absorbed, not that it helps.
Safety implication
1,8-cineole is also one of the compounds named as seizure-linked when oil is swallowed (see the Safety tab). No harm was reported in this study.
| Study | Result | People | Product |
|---|---|---|---|
| 20 | In 20 healthy adults, higher blood 1,8-cineole went with better speed and accuracy on thinking tasks and with a lower contentment score. There was no comparison group. |
Self-rated sleepiness score
Decrease in trials
A questionnaire score of how sleepy people feel; lower means less sleepy.
Low certaintyResults and what it means
Why it was measured
Main outcome in the nurse shift-work trial.
Statistical vs. clinical meaning
A symptom score, not a lab marker.
Safety implication
Feeling more alert does not mean it is safe to skip rest or to use the oil for long periods.
| Study | Result | People | Product |
|---|---|---|---|
| 21 | Mean score fell from 12.15 to 8.3 with rosemary scent and rose from 11.41 to 13.76 with water (P < 0.001). |
State anxiety score
Decrease in trials
A questionnaire score of how anxious a person feels right now; lower means less anxious.
Mixed findingsResults and what it means
Why it was measured
Main outcome in the surgery, kidney-stone and exam trials.
Statistical vs. clinical meaning
A symptom score, not a lab marker; results point both ways.
Safety implication
A scent that does not lower anxiety is no reason to use more of it.
| Study | Result | People | Product |
|---|---|---|---|
| 31 | Fell with rosemary scent before general surgery (P = 0.001). | ||
| 29 | No benefit during kidney-stone shockwave treatment; scores after treatment were higher in the scent groups than in the control group. | ||
| 9 | No clear difference between a lavender-rosemary inhaler and water in students (P = 0.10, 0.07). |
Hair count (scalp photographs)
Increase in trials
The number of hairs in a standard patch of scalp, measured from professional photographs.
Low certaintyResults and what it means
Why it was measured
Main outcome in the rosemary oil versus minoxidil trial.
Statistical vs. clinical meaning
A direct measure of hair, but the trial had no placebo group.
Safety implication
Scalp itching was higher than at the start in both groups.
| Study | Result | People | Product |
|---|---|---|---|
| 23 | No significant change at 3 months in either group; a significant rise from the start at 6 months in both groups; no significant difference between rosemary oil and minoxidil 2%. |
Finger skin temperature (infrared camera)
Increase in trials
How warm the fingertips are, measured with a thermal camera.
Very low certaintyResults and what it means
Why it was measured
Outcome in the Raynaud's pilot.
Statistical vs. clinical meaning
A physical measure, but the rise was as large with the olive oil control.
Safety implication
No adverse effects were observed in 12 people.
| Study | Result | People | Product |
|---|---|---|---|
| 32 | Temperature rose after both olive oil and rosemary oil; the difference between them was not significant. |
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 4
- Do not swallow rosemary essential oil. It is a concentrated oil and contains camphor.. The EU committee says rosemary oil is for skin use only. Poison Control warns that misused essential oils can cause serious poisoning, that choking on an oil can cause pneumonia, and that even a small amount of camphor swallowed is dangerous and can cause seizures within minutes. Rosemary oil contains camphor (EMA gives about 5 to 21 percent depending on the oil type). EMA found no reports of serious poisoning with rosemary oil itself, but it also found no clinical safety trials. If anyone swallows an essential oil, call poison control straight away. Regulatory 7 8 24
- People with epilepsy or past seizures should ask a doctor before using rosemary oil in any way.. A 2019 review and a 1999 case report paper name rosemary among essential oils that can trigger seizures when taken in, because of camphor and 1,8-cineole. The cases involved several oils and swallowing, not smelling. EMA says there are no human data supporting seizures from rosemary extracts taken by mouth. We found no report of a seizure from smelling rosemary oil or putting it on the skin, which is not the same as proof it cannot happen. The 2019 review lists an essential oil company affiliation. Review 3 4 8
- It can cause itching, rash and allergy, and breathing problems in some people.. EMA lists contact dermatitis and asthma-type breathing difficulty as possible effects of rosemary oil, frequency not known. Poison Control says rash is the most common allergic reaction to essential oils. A lab test predicts rosemary oil has some potential to sensitise skin. Case reports of rosemary allergy mostly involve the plant or extracts. Do not put the oil on broken or irritated skin or near the eyes or mouth. This page gives no dilutions or amounts; ask a pharmacist. Regulatory 7 24 22 18
- Not recommended in pregnancy, while breastfeeding, or for people under 18.. The EU committee advises against rosemary oil medicines in pregnancy and breastfeeding and for anyone under 18, because safety has not been established. Poison Control adds that children may be more susceptible to essential oils. Keep bottles locked away from children and pets. Regulatory 7 8 24
Side effects 4
| Effect | How often | Severity and recovery | Evidence |
|---|---|---|---|
| Allergic skin reaction (contact dermatitis) Published case reports are mostly about rosemary plant material and extracts, not the oil. | Frequency not known (EMA) | Not stated in the sources read Not stated in the sources read | Regulatory 7 18 |
| Asthma-type breathing difficulty (hypersensitivity) Healthy people showed no change in lung function tests after 15 minutes of nebulized oil, but that does not cover people with asthma. | Frequency not known (EMA) | Not stated Not stated | Regulatory 7 8 |
| Scalp itching Itching was less frequent with rosemary oil than with minoxidil in that trial. | Significantly higher than baseline at 3 and 6 months in a 100-person hair trial, in both the rosemary oil and minoxidil groups | Not stated Not stated | Controlled trial 23 |
| Eye and mucous membrane irritation EMA says avoid contact with the eyes and do not apply near mucous membranes. | Not known | Not stated Not stated | Regulatory 7 8 |
Liver
We found no case of liver injury from rosemary oil in the sources read. The EU committee advises caution with rosemary leaf taken by mouth in bile duct obstruction, gallstones and liver disease; that is the leaf, not the oil. A 2025 review of rosemary toxicity reports liver and kidney changes in mostly animal and high-amount studies. We did not read a LiverTox entry. 8 12
How often. Not established.
This is a safety connection. It is not evidence that Rosemary Oil supports liver health.
Medicines and supplements 4
| With | Why it matters | Importance | Evidence | What to do |
|---|---|---|---|---|
| Prescription and over-the-counter medicines medicines in general | EMA says no interactions with other medicines have been described in the literature at the time of assessment, and the assessment report says there are no data. Absence of reports is not proof of safety. | Regulatory Not enough evidence 7 8 | Tell your pharmacist you use rosemary oil, especially if you take medicines for epilepsy, heart or kidney disease. | |
| Medicines broken down by liver enzymes liver-enzyme medicines | Rodent studies suggest rosemary extracts may switch on some liver enzymes (CYP1A, 2B, 2E1, 3A) and the oil has not been tested. | Animal data on extracts only; no human or oil data. | Animal research Not enough evidence 8 | Ask a pharmacist if you take medicines with a narrow safety margin. |
| Epilepsy medicines and other medicines or products that affect seizure risk seizure-threshold medicines | Theoretical: camphor and 1,8-cineole are linked to seizures when swallowed, so any extra exposure could matter. | Our inference from the seizure reports; no interaction study was found. | Theoretical Not enough evidence 3 8 | Ask your doctor before using rosemary oil if you take epilepsy medicine. |
| Vapour rubs and other products that contain camphor other camphor products | Theoretical: rosemary oil contains camphor, so using several camphor products adds up. | Our inference; Poison Control describes camphor poisoning in children from skin products used more than the label said. | Theoretical Not enough evidence 24 8 | Do not combine camphor products without asking a pharmacist, and keep them away from children. |
Who should check first 7
| Situation | Advice | Evidence |
|---|---|---|
| Swallowing the essential oil | Do not swallow. If anyone may have swallowed any essential oil, call poison control or a doctor straight away. | Regulatory 7 24 |
| Epilepsy or a past seizure | Ask a doctor first. | Review 3 4 |
| Pregnancy or breastfeeding | EMA says not recommended because safety has not been established. | Regulatory 7 8 |
| Children and teenagers under 18 | EMA says not recommended for rosemary oil medicines for lack of data. | Regulatory 7 8 |
| Known allergy to rosemary, or heart or kidney disease | EMA says do not use rosemary oil medicines. | Regulatory 7 |
| Broken or irritated skin, eyes, mucous membranes | Do not apply. Broken skin is more prone to allergy and absorbs more (EMA). | Regulatory 8 7 |
| Asthma or sensitive airways | Ask a clinician first; EMA lists asthma-type reactions for the oil. | Regulatory 7 |
Overdose, product quality and regulators
Summary. Rat studies found the oil toxic at very high swallowed amounts (EMA). EMA found no reports of serious poisoning with rosemary or its oil, but also no clinical safety trials; the oil's camphor and cineole are the parts linked to seizures when swallowed.
Amounts. No safe amount is established, and this page gives none.
Onset and course. Not described for rosemary oil. For camphor in general, Poison Control says seizures can start within minutes of swallowing.
Repeated use. No data on long-term use of the oil. EMA's licensed oil medicines are skin products used for limited periods.
Animal data. Pets: the ASPCA lists the rosemary plant as non-toxic to dogs, cats and horses, but this is the plant, not the concentrated oil. We found no oil-specific guidance for cats or dogs. Ask a vet before using oils near pets.
Toxic parts. The oil is the concentrated form. Components linked to seizure concern when swallowed are camphor and 1,8-cineole.
Not read. Veterinary papers on rosemary oil in cats and dogs, any FDA or SCCS allergen listing, LiverTox and LactMed entries, and full texts of the seizure review and case reports were not read.
Essential oils are not tightly regulated, and rosemary oil comes in different chemical types.
Unknown species, strength and contaminants. Poison Control says it can be hard to know the plant species, concentration or contaminants in an essential oil bottle. 24
Different chemical types. The European Pharmacopoeia accepts two main types: a Spanish type with about 16 to 25 percent cineole and 13 to 21 percent camphor, and a Moroccan and Tunisian type with about 38 to 55 percent cineole and 5 to 15 percent camphor. Another type from France and Corsica is rich in alpha-pinene and verbenone. A trial result for one type does not carry over to another. 8
Look-alike names. Bog rosemary and wild or March rosemary (Ledum) are in the heather family and are not related to rosemary (EMA assessment report). 8
| Body | Action | Date |
|---|---|---|
| EMA Committee on Herbal Medicinal Products (HMPC) (European Union) | EU herbal monograph for rosemary oil skin medicines: traditional use for minor muscle and joint pain and minor leg circulation problems. Not for under 18s, in pregnancy or breastfeeding, with rosemary allergy, or with known heart or kidney disease; not near eyes or mucous membranes. Side effects: contact dermatitis, asthma-type reactions, frequency not known. source | 2024-09-20 |
| EMA HMPC public summary for rosemary oil (European Union) | Plain-language summary of the monograph above. source | 2026-03-12 |
| EMA HMPC assessment report (oil and leaf) (European Union) | Says no clinical studies exist for the traditional-use indications; serious poisoning not reported; no human data supporting seizures from rosemary extracts taken by mouth; use of the oil in under 18s and in pregnancy or breastfeeding not recommended; a European list entry cannot be supported because mutagenicity (Ames) data are missing. source | 2024-05-29 |
| Poison Control (US) (United States) | General essential-oil warning: keep out of reach of children and pets; stop and wash off if a rash appears; camphor is dangerous if swallowed. Rosemary oil is not named. source | n/a |
| ASPCA Animal Poison Control (United States) | Lists the rosemary plant as non-toxic to dogs, cats and horses. Plant listing only. source | n/a |
When to get medical help
- If a child, a pet or an adult may have swallowed essential oil, call poison control (1-800-222-1222 in the US) or emergency services straight away.
- Seizure, collapse, confusion or very slow breathing after any exposure: emergency help.
- Wheezing, chest tightness or trouble breathing after smelling the oil: stop and get medical help.
- Spreading rash, swelling of the face or lips, or blistering skin: stop using it and get medical help.
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
Is rosemary oil safe to swallow?
No. We do not advise swallowing essential oil. The EU committee says rosemary oil is for skin use only, and Poison Control warns that misused essential oils can cause serious poisoning. Rosemary oil contains camphor, which is dangerous swallowed. If anyone swallows an essential oil, call poison control straight away.
Can rosemary oil cause seizures?
A 2019 review and a 1999 case-report paper name rosemary among oils that can trigger seizures when taken in, because of camphor and 1,8-cineole. Those cases involved swallowing and several oils. We found no report of a seizure from smelling it or using it on skin, but that is not proof it cannot happen. People with epilepsy should ask a doctor first.
Is rosemary oil safe in pregnancy or for children?
Can rosemary oil cause an allergic reaction?
Does rosemary oil help hair grow?
One 6-month trial in 100 people found hair counts rose with rosemary oil about as much as with 2% minoxidil, with no placebo group. Nothing changed at 3 months. Reviews say the evidence is limited. It is not a replacement for seeing a doctor about hair loss. Scalp itching happened in the trial.
Does smelling rosemary improve memory?
Does rosemary oil lower anxiety?
Does rosemary oil keep you awake or alert?
Is rosemary oil safe for pets?
Is rosemary oil the same as rosemary tea or rosemary extract?
What do regulators say about rosemary oil?
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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 read the abstracts of 23 PubMed papers and the EMA assessment report (full text) and the EMA, Poison Control and ASPCA pages, checked the plant name in GBIF and the compounds in PubChem. We did not find or read a LiverTox, LactMed or FDA statement.
- 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. Where an author is linked to an essential oil company, this is labelled.
Sources 32
Each source was opened and checked. Where we read only the abstract, it says so. The small numbers in the text point here.
- ASPCA Animal Poison Control. Non-toxic plants: Rosemary. ASPCA website. . (full-text)
- Allam AT, El-Shiekh RA, El-Dessouki AM, et al. Pathophysiology, conventional treatments, and evidence-based herbal remedies of hair loss with a systematic review of controlled clinical trials. Naunyn Schmiedebergs Arch Pharmacol. 2025. PMID 40536553. DOI 10.1007/s00210-025-04286-6. (abstract)
- Bahr TA, Rodriguez D, Beaumont C, et al. The Effects of Various Essential Oils on Epilepsy and Acute Seizure: A Systematic Review. Evid Based Complement Alternat Med. 2019. PMID 31239862. DOI 10.1155/2019/6216745. (abstract)
- Burkhard PR, Burkhardt K, Haenggeli CA, et al. Plant-induced seizures: reappearance of an old problem. J Neurol. 1999. PMID 10460442. DOI 10.1007/s004150050429. (abstract)
- Can S, Yildirim Usta Y, Yildiz S, et al. The effect of lavender and rosemary aromatherapy application on cognitive functions, anxiety, and sleep quality in the elderly with diabetes. Explore (NY). 2024. PMID 39047346. DOI 10.1016/j.explore.2024.103033. (abstract)
- Dehghan N, Azizzadeh Forouzi M, Etminan A, et al. The effects of lavender, rosemary and orange essential oils on memory problems and medication adherence among patients undergoing hemodialysis: A parallel randomized controlled trial. Explore (NY). 2022. PMID 34736874. DOI 10.1016/j.explore.2021.10.004. (abstract)
- EMA Committee on Herbal Medicinal Products (HMPC). Rosmarini aetheroleum (rosemary oil): herbal medicinal product, EU herbal monograph and public summary. EMA herbal medicines page. 2024. (full-text)
- EMA Committee on Herbal Medicinal Products (HMPC). Assessment report on Rosmarinus officinalis L., aetheroleum and Rosmarinus officinalis L., folium (Final, Revision 1), EMA/HMPC/681037/2021. EMA/HMPC/681037/2021 (29 May 2024). 2024. (full-text)
- Enwright P, Blank S, Wells BM, et al. Effect of lavender and rosemary aromatherapy on test anxiety in chiropractic students. J Chiropr Educ. 2023. PMID 36306254. DOI 10.7899/JCE-21-44. (abstract)
- GBIF Secretariat. GBIF Backbone Taxonomy: Salvia rosmarinus Spenn., species key 10902460 (GBIF match API). GBIF species match API. 2026. (full-text)
- Gedney JJ, Glover TL, Fillingim RB. Sensory and affective pain discrimination after inhalation of essential oils. Psychosom Med. 2004. PMID 15272109. DOI 10.1097/01.psy.0000132875.01986.47. (abstract)
- Ghasemzadeh Rahbardar M, Hosseinzadeh H. Toxicity and safety of rosemary (Rosmarinus officinalis): a comprehensive review. Naunyn Schmiedebergs Arch Pharmacol. 2025. PMID 39096378. DOI 10.1007/s00210-024-03336-9. (abstract)
- Gupta AK, Wang H, Wang T, et al. Do Non-Prescription Products Help in Managing Androgenic Alopecia?. Skin Appendage Disord. 2025. PMID 40475103. DOI 10.1159/000542880. (abstract)
- Gupta AK, Bamimore MA, Talukder M. Relative Efficacy of Conventional Monotherapies and Select Nonconventional, Over-the-Counter Products for Male Androgenetic Alopecia: A Network Meta-Analysis Study. J Cosmet Dermatol. 2025. PMID 41051009. DOI 10.1111/jocd.70483. (abstract)
- Jimbo D, Kimura Y, Taniguchi M, et al. Effect of aromatherapy on patients with Alzheimer's disease. Psychogeriatrics. 2009. PMID 20377818. DOI 10.1111/j.1479-8301.2009.00299.x. (abstract)
- Köteles F, Babulka P. Role of expectations and pleasantness of essential oils in their acute effects. Acta Physiol Hung. 2014. PMID 25183507. DOI 10.1556/APhysiol.101.2014.3.8. (abstract)
- Köteles F, Babulka P, Szemerszky R, et al. Inhaled peppermint, rosemary and eucalyptus essential oils do not change spirometry in healthy individuals. Physiol Behav. 2018. PMID 29913229. DOI 10.1016/j.physbeh.2018.06.022. (abstract)
- Miroddi M, Calapai G, Isola S, et al. Rosmarinus officinalis L. as cause of contact dermatitis. Allergol Immunopathol (Madr). 2014. PMID 23827646. DOI 10.1016/j.aller.2013.04.006. (abstract)
- Moss M, Cook J, Wesnes K, et al. Aromas of rosemary and lavender essential oils differentially affect cognition and mood in healthy adults. Int J Neurosci. 2003. PMID 12690999. DOI 10.1080/00207450390161903. (abstract)
- Moss M, Oliver L. Plasma 1,8-cineole correlates with cognitive performance following exposure to rosemary essential oil aroma. Ther Adv Psychopharmacol. 2012. PMID 23983963. DOI 10.1177/2045125312436573. (abstract)
- Nasiri A, Boroomand MM. The effect of rosemary essential oil inhalation on sleepiness and alertness of shift-working nurses: A randomized, controlled field trial. Complement Ther Clin Pract. 2021. PMID 33550193. DOI 10.1016/j.ctcp.2021.101326. (abstract)
- Omeragic E, Dedic M, Elezovic A, et al. Application of direct peptide reactivity assay for assessing the skin sensitization potential of essential oils. Sci Rep. 2022. PMID 35523830. DOI 10.1038/s41598-022-11171-2. (abstract)
- Panahi Y, Taghizadeh M, Marzony ET, et al. Rosemary oil vs minoxidil 2% for the treatment of androgenetic alopecia: a randomized comparative trial. Skinmed. 2015. PMID 25842469. (abstract)
- Poison Control (National Capital Poison Center); Soloway RA, Troutman WG. Essential oils: Poisonous when misused. Poison Control website. . (full-text)
- PubChem, National Library of Medicine. PubChem compound record: 1,8-cineole (CID 2758). PubChem PUG REST. 2026. (full-text)
- PubChem, National Library of Medicine. PubChem compound record: camphor (CID 2537). PubChem PUG REST. 2026. (full-text)
- PubChem, National Library of Medicine. PubChem compound record: alpha-pinene (CID 6654). PubChem PUG REST. 2026. (full-text)
- PubChem, National Library of Medicine. PubChem compound record: borneol (CID 64685). PubChem PUG REST. 2026. (full-text)
- Rohi Ganji M, Jafari F, Rezaeian S, et al. The Effect of Inhalation Aromatherapy and Music Therapy on Anxiety in Patients Undergoing Shockwave Lithotripsy: A Randomized Controlled Clinical Trial. Evid Based Complement Alternat Med. 2022. PMID 35815287. DOI 10.1155/2022/8015798. (abstract)
- Sagorchev P, Lukanov J, Beer AM. Investigations into the specific effects of rosemary oil at the receptor level. Phytomedicine. 2010. PMID 20034774. DOI 10.1016/j.phymed.2009.09.012. (abstract)
- Sayadi Mank-Halati M, Rezaei M, Farzaei MH, et al. Comparing the effects of rosemary aromatherapy and music therapy on anxiety levels in patients undergoing general surgery: A randomized controlled clinical trial. Explore (NY). 2024. PMID 38242798. DOI 10.1016/j.explore.2024.01.002. (abstract)
- Vagedes J, Henes J, Deckers B, et al. Topical Rosmarinus officinalis L. in Systemic Sclerosis-Related Raynaud's Phenomenon: An Open-Label Pilot Study. Complement Med Res. 2022. PMID 35139518. DOI 10.1159/000522507. (abstract)
Where to buy
Check the label first. Whatever you buy, look for these:
- The botanical (Latin) name on the label and 100% pure oil
- A dark glass bottle and a batch number
- Essential oils are strong: dilute for skin, and do not swallow unless a qualified professional directs it
- Keep away from children and pets
Talk to a pharmacist or doctor before you start any supplement, especially if you take medicines. See the Safety tab for interactions.
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