Essential Oils & Aromatherapy · Essential oil
Tulsi (Holy Basil) Oil
Ocimum tenuiflorum L. (also called Ocimum sanctum) · also called Tulsi oil, holy basil oil, sacred basil oil
Tulsi oil is a concentrated essential oil distilled from holy basil, a plant revered in Ayurvedic and Siddha medicine. Most human studies of tulsi used leaf extracts taken by mouth, not the oil. For the oil itself there is one small trial, a dentist's dressing in children's baby teeth, plus lab work. The main caution: depending on the plant, the oil is rich in eugenol or in methyl eugenol, and it must never be swallowed.
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 Tulsi (Holy Basil) Oil
Tulsi oil is a concentrated oil distilled from holy basil. The human studies people quote for tulsi used leaf extracts taken by mouth, not the oil. For the oil there is one small trial in children's baby teeth and some lab work. Safety comes first: depending on the plant, the oil is rich in eugenol or in methyl eugenol, it must not be swallowed, and it can cause skin allergy.
What tulsi oil is
Tulsi, also called holy basil, is Ocimum tenuiflorum L. in the mint family (Lamiaceae). The older name Ocimum sanctum is a synonym in the GBIF plant database. It is not sweet basil (Ocimum basilicum), whose oil is mostly methyl chavicol and linalool.
The oil is a mixture, and the mix depends on the plant. A Nepal tulsi oil was about a third eugenol, with trans-beta-elemene (29% to 33%) and beta-caryophyllene (20% to 22%). Indian papers describe methyl eugenol-rich tulsi oils: 72.5% in one selection and 92.4% in another. Harvest method changed the methyl eugenol content in a third paper.
A small panel sniffing Thai basil oils found holy basil oils differ in scent from each other, but we do not describe the scent of tulsi oil because the abstract does not say which group each fell in.
What people use it for, and how strong the evidence is
For the oil itself, one randomised trial of 40 children found that a tulsi-oil dressing placed by a dentist in baby-tooth root canals lowered bacterial counts. An antibiotic paste did better, and saline rinsing also lowered counts. Bacterial counts are a lab marker, not tooth health.
Lab work shows tulsi oils slowing some germs and, in one screening test, keeping mosquitoes from landing. It also shows mixed antioxidant results. None of this has been tested in people for home use.
We found no trial of tulsi oil as a scent for stress, sleep or mood, and none on the skin.
Tulsi leaf extract is not tulsi oil
Two small trials gave healthy adults capsules of ethanol extract of tulsi leaf. One found higher immune blood markers after 4 weeks; the other found better scores on some reaction-time tests after 30 days. A review of 24 human studies of swallowed tulsi forms says all reported favourable results and no significant side effects, but it included theses and conference papers and gives no quality grade in the abstract.
These extracts are made differently and contain different compounds from the essential oil. Their results, and their safety record, do not carry over to the oil.
Tradition
Tulsi is highly revered in Ayurvedic and Siddha medicine, as the 2017 review puts it, and trial authors call it a sacred herb. We credit that tradition for the plant. We did not find a source describing the essential oil in those traditions.
Bottles, species and extracts are different things
Tulsi oil is not sweet basil oil, and it is not tree basil oil (eugenol 75.1% in one paper). Tulsi oils themselves differ: eugenol-rich in some samples, methyl eugenol-rich in others. Poison Control says it can be hard to know what is in a bottle. A label should give the Latin name Ocimum tenuiflorum, the plant part and country, and a batch test (GC-MS) listing eugenol and methyl eugenol.
What regulators say
IARC (2024) classes methyleugenol as probably carcinogenic to humans and notes its use as a flavouring is prohibited in the EU and USA. LiverTox covers eugenol. The FDA says aromatherapy products are regulated by intended use and that cosmetics need no pre-market approval. EFSA's 2023 clove-oil opinion, used here only as a comparison, says to treat clove oils as irritants and skin sensitisers and to minimise handler exposure to methyleugenol.
We did not find or read a statement from IFRA, EMA, NCCIH or LiverTox about tulsi oil.
At a glance
Traditional uses history, not proof
- The 2017 review of human tulsi studies says the plant is highly revered for its medicinal uses in the Ayurvedic and Siddha medical systems. That is about the plant and leaf.
- The authors of a 2011 trial describe tulsi as a sacred herb, and say it is traditionally believed that eating the leaf on an empty stomach raises immunity.
- We did not read a source on the essential oil in these traditions, so none is claimed.
Studied for research
- Bacteria in baby-tooth root canals, dentist-applied, very-low
- Germ-killing in the laboratory, insufficient
- Mosquito repellence in a lab screening test, insufficient
- Antioxidant action in test tubes, mixed results, insufficient
- Immune blood markers (leaf extract, not the oil), very-low
- Thinking tests (leaf extract, not the oil), very-low
Main compounds
- Eugenol, a main compound in some tulsi oils
- Methyl eugenol, a main compound in other tulsi oils
- trans-beta-Elemene
- beta-Caryophyllene
Common forms
- Essential oil (distilled from leaves or aerial parts)
- Scent from a diffuser
- Diluted skin-care and massage blends
- Not the same as tulsi tea, leaf or leaf extract capsules
Research links: Poison Control: Essential oils · Pet Poison Helpline: Essential oils · LiverTox: Eugenol (clove oil) · IARC: Methyleugenol, 2024 · Tulsi oils from Nepal, laboratory study (abstract) · Tulsi oil in children's baby teeth, trial (abstract) · Essential oils and contact allergy, review (abstract) · GBIF: Ocimum tenuiflorum · Research Library · Genes & Biomarkers Library
What it is and its history
- Accepted scientific name
- Ocimum tenuiflorum
- Naming authority
- L.
- Synonyms
- Ocimum sanctum L.
- Common names
- Tulsi (English); Holy basil (English); Sacred basil (English)
- Family or group
- Lamiaceae (the mint family), per GBIF. One 2025 paper calls the family Labiatae.
- Classification
- Plantae > Tracheophyta > Magnoliopsida > Lamiales > Lamiaceae > Ocimum > Ocimum tenuiflorum
- Native range
- The 2017 review says tulsi is indigenous to the Indian continent.
- Habitat
- Not checked in a source read.
- What it looks like
- Part used: Oils in the papers read were made from fresh leaves, flowering aerial parts or the aerial plant by hydro-distillation.
- Look-alikes and adulterants
- Name: Sweet basil (Ocimum basilicum); Note: A different species whose oil is mostly methyl chavicol and linalool; results for one do not carry to the other.; Name: Tree basil (Ocimum gratissimum); Note: An eugenol-rich basil (75.1% eugenol in one paper); different from tulsi.
- Sustainability and conservation
- Not checked (no IUCN or CITES source read).
Photographs
Traditional use and history history, not clinical proof
| Tradition or era | Documented use | Source |
|---|---|---|
| Ayurvedic and Siddha medicine | The 2017 review says tulsi is highly revered for its medicinal uses within the Ayurvedic and Siddha medical systems. This concerns the plant and leaf; we did not read a source on the essential oil in these traditions. | Jamshidi and Cohen 2017 (abstract) |
| Sacred herb | The authors of a 2011 trial describe tulsi as a sacred herb and say it is traditionally believed that eating the leaf on an empty stomach increases immunity. This is the authors' description of belief, about the leaf. | Mondal et al. 2011 (abstract) |
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 |
|---|---|---|---|---|
| Eugenol PubChem 3314 | phenylpropene (phenol) | Essential oil 32.15% to 34.95% in a Nepal tulsi oil; absent as a main compound in the methyl eugenol-rich oils. | Slowed some germs in the lab. A known skin sensitiser in a mouse test (EC3 5.4%). Blocked platelet activation in donor platelets and mice. High-dose ingestion can injure the liver. 29 16 10 13 2 | Laboratory |
| Methyl eugenol PubChem 7127 | phenylpropene | Essential oil 72.5% in one Indian tulsi selection and 92.4% in another oil; not a major compound in the Nepal oil. | Showed significant lab activity against Pseudomonas aeruginosa in one paper; no antioxidant activity. Classed by IARC as probably carcinogenic to humans (Group 2A). 29 8 17 5 | Laboratory |
| trans-beta-Elemene | sesquiterpene | Essential oil 29.08% to 32.85% in the Nepal tulsi oil. | No separate activity read. 16 | Laboratory |
| beta-Caryophyllene PubChem 5281515 | sesquiterpene | Essential oil 19.85% to 21.64% in the Nepal tulsi oil. | No separate activity read for tulsi; described as enantiomerically pure in the Nepal paper. 29 16 | Laboratory |
Mechanisms, receptors and pathways
| Target or pathway | Gene or receptor | What was found | Level |
|---|---|---|---|
| Bacterial and fungal growth (test tube) | Not specified | Tulsi oils slowed several germs in dishes, strongest against Candida albicans for the eugenol-rich Nepal oil. Methyl eugenol and eugenol alone each acted against different germs. 16 8 17 | Laboratory research |
| Radical-scavenging tests | Not specified | The eugenol-rich oil scored highest of three Ocimum oils; the methyl eugenol-rich oil scored very feebly in another paper. 16 8 | Laboratory research |
| Platelet activation (purified eugenol) | cPLA2 and NF-kB pathways, per the authors | Eugenol blocked platelet activation in donor platelets and had an anti-thrombotic effect in mice. 2 | In vitro / animal |
| Brain-protection and stress pathways (extracts) | Not specified | Reviews of lab and animal work on Ocimum extracts report effects on antioxidant enzymes, beta-amyloid and tau, and on stress pathways. Not specific to the oil. 22 20 | Animal / lab |
Absorption, metabolism and elimination
- Absorption
- Not established for tulsi oil in the sources read.
- Distribution
- Not established.
- Metabolism
- The FEMA panel review describes dose-dependent metabolic activation of methyl eugenol in rodents.
- Elimination
- Not established.
- Bioavailability
- Not established.
Isolated compounds versus whole extracts
The oil is a mixture, and its makeup changes with the plant, season and harvest method: eugenol-rich in one study, methyl eugenol-rich in others. It is also not the same as tulsi leaf, tea or leaf extract, which contain water- or alcohol-soluble compounds, so findings for those do not apply to the oil.
Nutritional composition
Tulsi oil is not a nutrient and is not an ingredient to swallow for health.
4 very low certainty5 not enough evidence
What is Tulsi (Holy Basil) Oil good for?
The uses people ask about and how strong the evidence is for each. Read the certainty label first: nothing here is better than very low. Results for tulsi leaf extract are marked and do not describe the oil.
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.
Bacteria in baby-tooth root canals (tulsi oil placed by a dentist)
Very low certaintyIn a trial of 40 children needing root-canal treatment of baby molars, a dressing of tulsi oil was followed by a significant drop in bacterial counts. A standard antibiotic paste worked better, and saline rinsing also lowered counts.
1 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
One randomised trial: 40 children, 20 per group, India. Tulsi oil versus triple antibiotic paste placed in the tooth for 3 days.
Results
Bacterial counts (CFU) fell significantly after the tulsi-oil dressing, and also after saline rinsing whichever dressing was used. The antibiotic paste had better antibacterial action than tulsi oil.
Effect sizes as reported
Statistically significant fall in CFU with tulsi oil; antibiotic paste better. Numbers not in the abstract.
Why this rating
One small trial of a lab marker (bacteria counts), not of tooth health. The oil is compared with an antibiotic paste that did better, and saline alone also lowered counts, so it is hard to credit the oil.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Children with infected baby molars, in dental care.
Limits
A dentist-applied dressing inside a tooth. It does not support home use, scent or skin use. The abstract does not give the oil strength.
Why researchers looked
Dentists look for gentler dressings for baby teeth than antibiotic pastes.
Traditional use
None stated in the abstract.
Proposed mechanism Preliminary mechanism
Not established; the oil is thought to slow bacteria (see the lab results).
A proposed mechanism does not show that the effect happens in people.
This is a clinical dental use. It does not show that the oil is safe to put on skin or gums at home. Eugenol-rich oils can cause allergy (see Safety).
Germ-killing in the laboratory
Not enough evidenceIn test tubes, tulsi oils slowed some bacteria and fungi, and one tulsi oil acted strongly against Candida albicans. Which germs were slowed differed between oils.
3 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
No human study of this lab result; the only trial is the dental one above.
Results
A Nepal tulsi oil (eugenol-rich) showed the strongest antimicrobial action of three Ocimum oils, especially against Candida albicans. A methyl eugenol-rich tulsi oil showed significant activity against A. niger and S. faecalis. A third paper reports broad antibacterial and antifungal action for oils of 14 Ocimum selections including tulsi.
Effect sizes as reported
Lab measures only; tulsi-only figures were not in all abstracts.
Why this rating
Test-tube work on three differently made oils. Lab germ-killing does not show an effect in or on a person.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
No people.
Limits
Different tulsi oils have very different chemistry (eugenol-rich vs methyl eugenol-rich), so one result does not carry to another bottle.
Why researchers looked
To see whether the oil could act as a natural preservative or antiseptic.
Traditional use
None stated.
Proposed mechanism Preliminary mechanism
Compounds such as eugenol and methyl eugenol slow germs in the lab; the mechanism in a body is not established.
A proposed mechanism does not show that the effect happens in people.
Lab results are not advice to use the oil on skin or in the mouth.
Mosquito repellence (lab screening)
Not enough evidenceIn one lab screening test, a 20% solution of tulsi leaf oil in ethanol stopped Aedes aegypti mosquitoes landing for up to 6 hours, similar to 20% DEET.
1 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
Not a trial of safety or protection in people; the abstract describes a repellency screening test.
Results
No mosquito landing up to 6 hours with 20% O. sanctum oil, comparable to 20% DEET; a 5% four-oil blend also had no landing up to 6 hours.
Effect sizes as reported
No landing at 6 hours in the test.
Why this rating
One screening test, one mosquito species, from the leaf oil. It does not test skin reactions, other mosquitoes, or real-world protection.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Mosquitoes.
Limits
A 20% ethanol solution is a laboratory test strength, not a use recommendation; this page gives no dilution.
Why researchers looked
Mosquito-borne disease is a big problem in India, and people look for plant-based repellents.
Traditional use
None stated.
Proposed mechanism Preliminary mechanism
Not established.
A proposed mechanism does not show that the effect happens in people.
Eugenol-rich oils can cause skin allergy. A repellent test does not show an oil is safe to put on skin.
Antioxidant action (lab tests)
Not enough evidenceIn chemistry tests, a Nepal tulsi oil had the strongest antioxidant activity of three Ocimum oils, but a methyl eugenol-rich tulsi oil showed very feeble activity in another paper.
2 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
No human study.
Results
Nepal oil (eugenol 32-35%): DPPH IC50 69.23 +/- 0.10 ug/mL and ABTS IC50 9.05 +/- 0.24 ug/mL, the highest of the three species. Indian oil (methyl eugenol 92.4%): very feeble antioxidant activity.
Effect sizes as reported
Lab numbers only.
Why this rating
Two lab papers disagree, and test-tube antioxidant results are poor predictors of health effects.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
No people.
Limits
Chemistry differs between tulsi oils, which probably explains the disagreement.
Why researchers looked
Antioxidant tests are cheap, common first checks on plant oils.
Traditional use
None stated.
Proposed mechanism Preliminary mechanism
Test-tube radical-scavenging assays (DPPH, ABTS); nothing measured in a body.
A proposed mechanism does not show that the effect happens in people.
None.
Immune blood markers (tulsi LEAF extract capsules, not the oil)
Very low certaintyIn 22 healthy adults, capsules of tulsi leaf extract raised some immune blood markers compared with placebo after 4 weeks. This was the leaf extract taken by mouth, not the essential oil.
1 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
One double-blind, placebo-controlled cross-over trial, 24 enrolled and 22 analysed, New Delhi.
Results
After 4 weeks, interferon-gamma (p=0.039), interleukin-4 (p=0.001), T-helper cells (p=0.001) and NK cells (p=0.017) were higher on tulsi extract than placebo.
Effect sizes as reported
Statistically significant differences in lab markers; effect sizes not in the abstract.
Why this rating
One small trial in healthy people measuring lab markers, not infections or illness. Leaf extract does not tell us about the oil.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Healthy adult volunteers.
Limits
Not about the oil. No information on colds or other illness.
Why researchers looked
Tulsi leaf is traditionally believed to support immunity; the trial authors describe it as a sacred herb and say taking the leaf on an empty stomach is believed to raise immunity.
Traditional use
Described by the trial authors as traditional belief; no earlier source was read.
Proposed mechanism Preliminary mechanism
Not established in people; the trial measured immune cell and cytokine levels.
A proposed mechanism does not show that the effect happens in people.
Does not apply to the essential oil.
Thinking tests and stress measures (tulsi LEAF extract capsules, not the oil)
Very low certaintyIn healthy adults, 30 days of tulsi leaf extract capsules was followed by better scores than placebo on some reaction-time and error tests. Cortisol and anxiety scores changed over time in the extract group, but the difference from placebo was significant only for one brain-wave timing measure.
1 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
One placebo-controlled randomised trial in healthy volunteers, 30 days; the number of people is not in the abstract.
Results
Between groups: better reaction time and error rate on several Sternberg and Stroop measures. Within the extract group only: P300 latency, salivary cortisol and anxiety scores improved over time, but the difference from placebo was significant for P300 latency alone. No change in heart rate or skin conductance.
Effect sizes as reported
Better test scores than placebo on several measures; numbers not in the abstract.
Why this rating
Short trial in healthy people, unclear size, and only some measures differed from placebo. Leaf extract by mouth; it does not describe smelling or using the oil.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Healthy adults.
Limits
Not about the oil. The conclusion ("seems to have potential") is more positive than the between-group results.
Why researchers looked
Animal work had suggested tulsi helps thinking and stress; the authors say there were few human studies.
Traditional use
Not stated.
Proposed mechanism Preliminary mechanism
Not established.
A proposed mechanism does not show that the effect happens in people.
Does not apply to the essential oil.
Many health outcomes (24 studies of swallowed tulsi forms, not the oil)
Very low certaintyA review of 24 human studies of tulsi taken by mouth says all reported favourable outcomes and none reported significant side effects. The authors say dose, form and who benefits are still unclear.
1 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
One systematic review of 24 human studies, including books, theses and conference papers; the abstract does not mention the oil.
Results
All 24 studies reported favourable clinical outcomes and none reported significant adverse events. The review says further studies are needed to explore mechanisms and clarify dosage and dose form.
Effect sizes as reported
Not given in the abstract.
Why this rating
Many small, varied studies, with no quality grade in the abstract, and uniformly favourable results are a warning sign for bias. It does not cover the oil.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Mixed groups.
Limits
The abstract mentions diabetes, metabolic syndrome and psychological stress as suggestions; those are not tested for the oil.
Why researchers looked
Tulsi is highly revered in Ayurvedic and Siddha medicine, as the review puts it.
Traditional use
The review authors credit Ayurvedic and Siddha systems.
Proposed mechanism Preliminary mechanism
Not established.
A proposed mechanism does not show that the effect happens in people.
Does not apply to the essential oil.
Brain protection (lab and animal models)
Not enough evidenceReviews of lab and animal experiments say Ocimum extracts increased antioxidant enzymes and reduced beta-amyloid and tau in models of Alzheimer-type disease. No human evidence of this was read.
2 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
None.
Results
The 2025 review says Ocimum extracts raised antioxidant enzymes and reduced beta-amyloid and tau in experiments and that more research is needed. A 2026 review of adaptogen mechanisms includes Ocimum tenuiflorum and says further clinical studies are needed.
Effect sizes as reported
Not applicable.
Why this rating
Cell and animal work, mostly on extracts, not on the essential oil.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
No people.
Limits
Not specific to the oil.
Why researchers looked
There are few treatments for Alzheimer-type disease, so researchers screen plants.
Traditional use
None stated.
Proposed mechanism Preliminary mechanism
Antioxidant enzymes, beta-amyloid and tau in models; mechanisms review also covers stress pathways.
A proposed mechanism does not show that the effect happens in people.
None.
Effects on breast-cancer cells in a dish (lab)
Not enough evidenceIn one lab paper, a tulsi oil was toxic to breast-cancer cells in a dish, with lower toxicity to normal cells. This is cell work and not a treatment.
1 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
None.
Results
Against MCF-7 breast-cancer cells the IC50 was 23.43 ug/mL, with lower toxicity to normal NIH-3T3 cells.
Effect sizes as reported
IC50 23.43 ug/mL in cells.
Why this rating
One cell experiment. Many substances kill cells in a dish; this does not show any effect on cancer in a person.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
No people.
Limits
Not a cancer treatment or sign of one.
Why researchers looked
Lab screening of plant oils for cell-killing activity.
Traditional use
None stated.
Proposed mechanism Preliminary mechanism
Cell-toxicity (CCK-8) assay.
A proposed mechanism does not show that the effect happens in people.
Do not use essential oils as a cancer treatment.
Connections to the rest of health
How Tulsi (Holy Basil) 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 |
|---|---|---|---|---|
| Immune Support | Very low certainty | Bacteria in baby-tooth root canals (tulsi oil placed by a dentist): In a trial of 40 children needing root-canal treatment of baby molars, a dressing of tulsi oil was followed by a significant drop in bacterial counts. A standard antibiotic paste worked better, and saline rinsing also lowered counts. | 1 | |
| Immune Support | Not enough evidence | Germ-killing in the laboratory: In test tubes, tulsi oils slowed some bacteria and fungi, and one tulsi oil acted strongly against Candida albicans. Which germs were slowed differed between oils. | 16 8 17 | |
| Seasonal Wellness | Not enough evidence | Mosquito repellence (lab screening): In one lab screening test, a 20% solution of tulsi leaf oil in ethanol stopped Aedes aegypti mosquitoes landing for up to 6 hours, similar to 20% DEET. | 11 | |
| Cellular Protection | Not enough evidence | Antioxidant action (lab tests): In chemistry tests, a Nepal tulsi oil had the strongest antioxidant activity of three Ocimum oils, but a methyl eugenol-rich tulsi oil showed very feeble activity in another paper. Effects on breast-cancer cells in a dish (lab): In one lab paper, a tulsi oil was toxic to breast-cancer cells in a dish, with lower toxicity to normal cells. This is cell work and not a treatment. | 16 8 | |
| Immune Support | Very low certainty | Immune blood markers (tulsi LEAF extract capsules, not the oil): In 22 healthy adults, capsules of tulsi leaf extract raised some immune blood markers compared with placebo after 4 weeks. This was the leaf extract taken by mouth, not the essential oil. | 14 | |
| Stress Reduction | Very low certainty | Thinking tests and stress measures (tulsi LEAF extract capsules, not the oil): In healthy adults, 30 days of tulsi leaf extract capsules was followed by better scores than placebo on some reaction-time and error tests. Cortisol and anxiety scores changed over time in the extract group, but the difference from placebo was significant only for one brain-wave timing measure. | 18 | |
| Better Focus | Very low certainty | Thinking tests and stress measures (tulsi LEAF extract capsules, not the oil): In healthy adults, 30 days of tulsi leaf extract capsules was followed by better scores than placebo on some reaction-time and error tests. Cortisol and anxiety scores changed over time in the extract group, but the difference from placebo was significant only for one brain-wave timing measure. | 18 | |
| Holistic Balance | Very low certainty | Many health outcomes (24 studies of swallowed tulsi forms, not the oil): A review of 24 human studies of tulsi taken by mouth says all reported favourable outcomes and none reported significant side effects. The authors say dose, form and who benefits are still unclear. | 6 | |
| Brain Health | Not enough evidence | Brain protection (lab and animal models): Reviews of lab and animal experiments say Ocimum extracts increased antioxidant enzymes and reduced beta-amyloid and tau in models of Alzheimer-type disease. No human evidence of this was read. | 22 20 |
B. Body systems
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Immune System | Biological association | Very low certainty | Studied for: Bacteria in baby-tooth root canals (tulsi oil placed by a dentist) Studied for: Germ-killing in the laboratory | 1 16 8 17 14 |
| Integumentary System | Biological association | Not enough evidence | Studied for: Mosquito repellence (lab screening) | 11 |
| Whole Body Balance | Biological association | Not enough evidence | Studied for: Antioxidant action (lab tests) Studied for: Many health outcomes (24 studies of swallowed tulsi forms, not the oil) | 16 8 6 |
| Brain Focus | Biological association | Very low certainty | Studied for: Thinking tests and stress measures (tulsi LEAF extract capsules, not the oil) Studied for: Brain protection (lab and animal models) | 18 22 20 |
| Stress Mood | Biological association | Very low certainty | Studied for: Thinking tests and stress measures (tulsi LEAF extract capsules, not the oil) | 18 |
E. Health conditions
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Contact dermatitis | Adverse effect or risk | Documented risk | Eugenol is a skin sensitiser in a mouse test; essential oils are a known cause of contact allergy, mostly from pure or concentrated products. Eugenol is a skin sensitiser in a mouse test; essential oil contact allergy mostly follows pure or concentrated products. Preparation or compound: Eugenol-rich essential oils on the skin |
10 24 |
| Pregnancy | Not enough evidence | Safety in pregnancy not clearly demonstrated; no tulsi-oil data. Preparation or compound: Essential oils in general; tulsi leaf extract in rats |
12 23 |
I. Biomarkers
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Bacterial counts (CFU) in the root canal | Biological association | Very low certainty | Measured in trials: decrease. A lab change is not the same as a health benefit. | 1 |
| Mosquito landing and feeding (repellency test) | Biological association | Not enough evidence | Measured in trials: decrease. A lab change is not the same as a health benefit. | 11 |
| Interferon-gamma, interleukin-4, T-helper and NK cells (leaf extract trial) | Biological association | Very low certainty | Measured in trials: increase. A lab change is not the same as a health benefit. | 14 |
| Reaction time and error rate on thinking tests, P300 latency (leaf extract trial) | Biological association | Very low certainty | Measured in trials: improve. A lab change is not the same as a health benefit. | 18 |
L. Active compounds
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Eugenol | Biological association | Laboratory | Slowed some germs in the lab. A known skin sensitiser in a mouse test (EC3 5.4%). Blocked platelet activation in donor platelets and mice. High-dose ingestion can injure the liver. Preparation or compound: Essential oil |
29 16 10 13 2 |
| Methyl eugenol | Biological association | Laboratory | Showed significant lab activity against Pseudomonas aeruginosa in one paper; no antioxidant activity. Classed by IARC as probably carcinogenic to humans (Group 2A). Preparation or compound: Essential oil |
29 8 17 5 |
| trans-beta-Elemene | Biological association | Laboratory | No separate activity read. Preparation or compound: Essential oil |
16 |
| beta-Caryophyllene | Biological association | Laboratory | No separate activity read for tulsi; described as enantiomerically pure in the Nepal paper. Preparation or compound: Essential oil |
29 16 |
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).
The evidence
The research centre for Tulsi (Holy Basil) 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 24 PubMed records, the Poison Control, Pet Poison Helpline and FDA pages, and checked the plant name in GBIF and three compounds in PubChem. We did not find or read a LiverTox, LactMed, IFRA or EMA statement for tulsi oil.
Study library: every study we checked 29
| Study | Design | People | Product, dose, length | Result |
|---|---|---|---|---|
| Ahirwar 2018 A clinical trial comparing antimicrobial efficacy of "essential oil of Ocimum sanctum" with triple antibiotic paste as an intracanal medicament in primary molars J Indian Soc Pedod Prev Dent · PMID 29970638 · DOI |
Randomised clinical trial human (children) |
40 Children needing root-canal treatment of baby (primary) molars, India |
Essential oil of Ocimum sanctum (tulsi) placed in the tooth canal by the dentist not stated Not repeated here 3 days of dressing in the tooth · vs Triple antibiotic paste (TAP) |
20 children per group. The tulsi-oil dressing was followed by a statistically significant fall in bacterial counts. Saline rinsing also lowered counts whichever dressing was used. The antibiotic paste showed better antibacterial action than the tulsi oil. Fall in CFU with tulsi oil; antibiotic paste was better Methods, limits and fundingOutcomes: Bacterial counts (colony-forming units, CFU) in the root canal, aerobic and anaerobic Limitations: Small trial of a dentist-applied dressing inside a baby tooth, a very different use from home aromatherapy. Bacterial counts are a lab marker, not tooth health. The abstract does not give the oil strength or the number of CFU. Funding and conflicts: The authors reported no conflicts of interest. Read: abstract |
| Chang 2024 Eugenol: A Potential Modulator of Human Platelet Activation and Mouse Mesenteric Vascular Thrombosis via an Innovative cPLA2-NF-kB Signaling Axis Biomedicines · PMID 39200154 · DOI |
Laboratory and mouse study mixed (lab, mouse) |
Platelets from healthy human donors; mice | Eugenol (a compound from clove oil) n/a Not repeated here n/a · vs n/a |
The authors report eugenol blocked platelet activation in donor platelets and had an anti-thrombotic effect in mice, via the cPLA2 and NF-kB pathways. Not applicable Methods, limits and fundingOutcomes: Platelet activation and clot formation Limitations: Lab and mouse work with purified eugenol. It does not show an effect from tulsi oil in people. Funding and conflicts: Not stated in the abstract excerpt read. Read: abstract |
| EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) 2023 Safety and efficacy of feed additives consisting of essential oils derived from the flower buds or the leaves of Syzygium aromaticum (clove bud oil and clove leaf oils) for all animal species EFSA Journal · PMID 37522096 · DOI |
Regulatory scientific opinion human (regulatory) |
Animal species (feed additive); also user and consumer safety | Clove bud and clove leaf oils flower bud, leaf Not repeated here n/a · vs n/a |
Clove oils contain methyleugenol (up to 0.13%). EFSA says the additives should be considered irritant to skin, eyes and the respiratory tract and as skin sensitisers, and that exposure of unprotected users to methyleugenol may occur, so user exposure should be minimised. Not applicable Methods, limits and fundingOutcomes: Safety for animals, consumers, users Limitations: About clove oil as animal-feed additive, used here only as a comparison for handling advice. It is not about tulsi oil. Funding and conflicts: Regulator opinion. Read: abstract |
| Geier 2022 Contact sensitization to essential oils: IVDK data of the years 2010-2019 Contact Dermatitis · PMID 35417610 · DOI |
Retrospective patch test database analysis |
10930 Dermatitis patients in German-speaking skin clinics |
Twelve essential oils patch tested n/a Not repeated here 2010-2019 · vs n/a |
Of 10,930 patients, 908 (8.3%) reacted to at least one of the 12 oils tested. Tulsi oil is not among the oils named in the part of the abstract read. 8.3% reacted to at least one oil Methods, limits and fundingOutcomes: Rate of positive patch tests Limitations: Patients with suspected dermatitis, not the general public. Only part of the abstract was read. Funding and conflicts: Not stated. Read: abstract |
| IARC Working Group on the Identification of Carcinogenic Hazards to Humans 2024 Aspartame, Methyleugenol, and Isoeugenol (IARC Monographs volume) IARC Monographs · PMID 39715313 |
Authoritative guidance (hazard classification) human (regulatory) |
Evidence review of human, animal and mechanistic studies | Methyleugenol n/a Not repeated here n/a · vs n/a |
The IARC Working Group concluded that methyleugenol is probably carcinogenic to humans (Group 2A). The abstract says methyleugenol occurs naturally in essential oils of various plants and is used in cosmetics; its use as a flavouring is prohibited in the EU and the USA, but it is still present in foods and consumer products through natural occurrence in herbs and spices. Hazard classification, not a risk figure Methods, limits and fundingOutcomes: Cancer hazard classification Limitations: A hazard grade says how strong the evidence is that something can cause cancer, not how likely it is at any given exposure. It does not mention tulsi oil. Funding and conflicts: International Agency for Research on Cancer (WHO). Read: abstract |
| Jamshidi 2017 The Clinical Efficacy and Safety of Tulsi in Humans: A Systematic Review of the Literature Evid Based Complement Alternat Med · PMID 28400848 · DOI |
Systematic review review |
Human studies of tulsi taken by mouth (24 found), for metabolic, heart, immune and brain outcomes | Tulsi taken by mouth in several forms (leaf, extracts and others); the abstract does not mention the oil leaf and others Not repeated here Varied · vs Varied |
The authors found 24 studies. All reported favourable clinical outcomes and none reported significant adverse events. They say further studies are needed to explore mechanisms, clarify the dosage and form, and find who is most likely to benefit. All 24 studies favourable (as the authors report) Methods, limits and fundingOutcomes: Clinical outcomes and adverse events Limitations: The abstract says the search included books, theses and conference papers, and gives no quality grade. A uniformly favourable set of small studies can reflect publication bias. It is about tulsi taken by mouth, not the oil. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Janes 2005 Essential oil poisoning: N-acetylcysteine for eugenol-induced hepatic failure and analysis of a national database Eur J Pediatr · PMID 15895251 · DOI |
Case report with database analysis human (children) |
1 A 15-month-old boy (UK) |
Clove oil swallowed (about 10 ml) n/a Not repeated here n/a · vs n/a |
The child developed fulminant liver failure after swallowing 10 ml of clove oil (ALT above 13,000 U/L at 24 hours). It resolved after hospital treatment with intravenous N-acetylcysteine. A national database showed a 14-fold rise in home accidents related to aromatherapy between 1994 and 1999. Single case Methods, limits and fundingOutcomes: Liver failure and treatment Limitations: One case of a different eugenol-rich oil (clove). It does not show the same would happen with tulsi oil. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Joshi 2013 Chemical Composition, In Vitro Antimicrobial and Antioxidant Activities of the Essential Oils of Ocimum Gratissimum, O. Sanctum and their Major Constituents Indian J Pharm Sci · PMID 24302801 · DOI |
Laboratory study laboratory |
Oils from flowering aerial parts, tested in the lab | Essential oil of Ocimum sanctum (= O. tenuiflorum), flowering aerial parts flowering aerial parts Not repeated here n/a · vs O. gratissimum oil; pure eugenol and methyl eugenol |
The principal constituent of the O. sanctum oil was methyl eugenol (92.4%); the O. gratissimum oil was mostly eugenol (75.1%). O. sanctum oil showed significant activity against A. niger and S. faecalis. Its antioxidant activity was described as very feeble, and methyl eugenol alone showed none. Lab measures only Methods, limits and fundingOutcomes: Composition (GC, GC-MS), antimicrobial tube-dilution tests, antioxidant assays Limitations: Test-tube work; a different oil type from the eugenol-rich Nepal oil. Not tested in people. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Kothari 2004 Essential oil yield and quality of methyl eugenol rich Ocimum tenuiflorum L.f. (syn. O. sanctum L.) grown in south India as influenced by method of harvest J Chromatogr A · PMID 15553132 · DOI |
Field experiment plant |
Crop grown in Hyderabad, India | Essential oil of methyl eugenol-rich Ocimum tenuiflorum L.f. aerial plant Not repeated here Four harvests in one year · vs Three harvest methods |
The way the plant was cut changed the oil: harvesting shoot biomass at 30 cm above ground gave the highest methyl eugenol, and the content fell for primary branch and secondary branch harvests. The abstract does not give the methyl eugenol percentage. Not applicable Methods, limits and fundingOutcomes: Oil yield and composition by method of harvest Limitations: Crop study, not a health study. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Lalko 2006 Investigation of the dermal sensitization potential of various essential oils in the local lymph node assay Food Chem Toxicol · PMID 16324777 · DOI |
Animal (mouse) test mouse |
Mice; seven essential oils and three single compounds | Basil, citronella, clove leaf, geranium, litsea cubeba, lemongrass and palmarosa oils; citral, eugenol and geraniol n/a Not repeated here n/a · vs Vehicle |
Eugenol gave an EC3 of 5.4%, and the authors say each oil was generally about as potent as its main single compound. Tulsi oil was not tested. EC3 for eugenol 5.4% Methods, limits and fundingOutcomes: Skin sensitisation potency (EC3) Limitations: Mouse test with fragrance-industry authors (Research Institute for Fragrance Materials). The basil oil was not stated to be tulsi, so only the eugenol result is used here. Funding and conflicts: Fragrance-industry research institute (RIFM). Read: abstract |
| Lalthazuali 2017 Mosquito repellent activity of volatile oils from selected aromatic plants Parasitol Res · PMID 28013374 · DOI |
Laboratory repellency screening laboratory |
Aedes aegypti mosquitoes (female adults), in a repellency test following an ICMR protocol | Essential oil of Ocimum sanctum leaves (hydro-distilled), 20% in ethanol; also a 5% four-oil blend fresh leaf Not repeated here Up to 6 hours of observation · vs 20% DEET in ethanol; ethanol (negative control) |
With 20% O. sanctum oil, no mosquito landed for up to 6 hours, comparable to 20% DEET. A 5% blend of four oils (including O. sanctum) also had no landing up to 6 hours. No landing at 6 hours in the test Methods, limits and fundingOutcomes: Mosquito landing and feeding Limitations: One mosquito species, a screening test. The abstract does not say whether the test surface was skin, and it did not test skin reactions. Results for a 20% ethanol solution do not describe safe use. Funding and conflicts: Government research centre (ICMR Vector Control Research Centre); no commercial funding stated in the abstract. Read: abstract |
| Lis-Balchin 1999 Possible health and safety problems in the use of novel plant essential oils and extracts in aromatherapy J R Soc Promot Health · PMID 10673845 · DOI |
Narrative review review |
Aromatherapy practice | Essential oils in general n/a Not repeated here n/a · vs n/a |
Commonly used oils in massage are seldom dangerous at 2% dilution if not adulterated, but safety during pregnancy, childbirth and in babies has not been clearly demonstrated. Sensitisation is a growing concern. Not applicable Methods, limits and fundingOutcomes: Safety in aromatherapy Limitations: Old (1999) and general; tulsi oil is not mentioned. Funding and conflicts: Not stated. Read: abstract |
| LiverTox 2012 Eugenol (Clove Oil). LiverTox: Clinical and Research Information on Drug-Induced Liver Injury LiverTox (NIDDK), record updated 2019 · PMID 31869191 |
Authoritative guidance human (regulatory) |
Reference record on eugenol / clove oil | Eugenol n/a Not repeated here n/a · vs n/a |
Eugenol in therapeutic doses has not been implicated in clinically apparent liver injury, but ingestions of high doses, as in an overdose, can cause severe liver injury. Not applicable Methods, limits and fundingOutcomes: Liver injury from eugenol Limitations: About eugenol and clove oil. It does not mention tulsi oil. Funding and conflicts: Public (US NIH) resource. Read: abstract |
| Mondal 2011 Double-blinded randomized controlled trial for immunomodulatory effects of Tulsi (Ocimum sanctum Linn.) leaf extract on healthy volunteers J Ethnopharmacol · PMID 21619917 · DOI |
Randomised double blind placebo controlled cross over trial |
24 Healthy volunteers (22 analysed), New Delhi, India |
Ethanolic extract of tulsi LEAF in capsules (NOT the essential oil) leaf Not repeated here 4 weeks · vs Placebo capsules |
After 4 weeks, interferon-gamma (p=0.039), interleukin-4 (p=0.001), T-helper cells (p=0.001) and NK cells (p=0.017) were higher on tulsi extract than on placebo. Lab marker differences; no effect sizes in the abstract Methods, limits and fundingOutcomes: Cytokines (interferon-gamma, interleukin-4) and immune cell percentages in blood Limitations: Small trial in healthy people, lab markers rather than illness. Leaf extract by mouth, so it says nothing about the oil, scent or skin use. Funding and conflicts: Not stated in the abstract. Read: abstract |
| National Toxicology Program 2000 NTP Toxicology and Carcinogenesis Studies of Methyleugenol (CAS NO. 93-15-2) in F344/N Rats and B6C3F1 Mice (Gavage Studies) Natl Toxicol Program Tech Rep Ser · PMID 12563349 |
Animal study (2 year) mixed (rat, mouse) |
Rats and mice | Methyleugenol (about 99% pure) by stomach tube n/a Not repeated here 14 weeks and 2 years · vs Vehicle controls |
In mice, methyleugenol increased liver tumours (hepatocellular adenoma and carcinoma, hepatoblastoma, among others). In rats, liver injury markers rose at higher doses in the 14-week study, and in the 2-year study male rats had more tumour types, including kidney tubule lesions, mesothelioma, mammary and skin-tissue tumours. Increased tumour rates in animals Methods, limits and fundingOutcomes: Tumours and tissue damage Limitations: Large doses given by stomach tube to animals. It does not describe scent or skin use, and it does not mention tulsi oil. Funding and conflicts: US government programme. Read: abstract |
| Paudel 2025 Seasonal Variation in Essential Oil Composition and Bioactivity of Three Ocimum Species from Nepal Molecules · PMID 40942106 · DOI |
Laboratory study laboratory |
Oils from O. tenuiflorum, O. basilicum and O. americanum grown in Nepal; cell lines | Essential oil of Ocimum tenuiflorum L., hydro-distilled aerial plant (not stated in abstract) Not repeated here Seasonal samples · vs Two other Ocimum oils |
Tulsi oil yield was highest in autumn (1.67 +/- 0.13%). Main compounds: eugenol 32.15-34.95%, trans-beta-elemene 29.08-32.85%, beta-caryophyllene 19.85-21.64%. Of the three species, tulsi oil showed the strongest antimicrobial action, particularly against Candida albicans, and the highest antioxidant activity (DPPH IC50 69.23 +/- 0.10 ug/mL; ABTS IC50 9.05 +/- 0.24 ug/mL). Against breast-cancer cells (MCF-7) the IC50 was 23.43 ug/mL, with lower toxicity to normal cells. Lab measures only Methods, limits and fundingOutcomes: Oil yield, chemistry (GC-MS), antioxidant, antimicrobial and cell-toxicity tests in the lab Limitations: Test-tube and cell work. Nothing was tested in people or animals. Chemistry differs between oils (see the methyl eugenol-rich oils in other papers). Funding and conflicts: The authors declared no conflicts of interest. Read: abstract |
| Rao 2011 Chemical and biological diversity in fourteen selections of four Ocimum species Nat Prod Commun · PMID 22224293 |
Laboratory/field study laboratory |
Fourteen plant selections grown in India | Essential oil of Ocimum tenuiflorum L.f. (syn. O. sanctum), selection T13 aerial plant Not repeated here n/a · vs Other Ocimum species |
The tulsi selection (T13) gave an oil with methyl eugenol 72.5% and a yield of 171.7 kg/ha. The oils showed broad-spectrum antibacterial and antifungal action in the lab; the abstract does not give tulsi-only figures. Lab measures only Methods, limits and fundingOutcomes: Oil yield, composition, antibacterial and antifungal tests Limitations: One tulsi selection. Tulsi-specific antimicrobial numbers were not in the abstract. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Sampath 2015 Holy basil (Ocimum sanctum Linn.) leaf extract enhances specific cognitive parameters in healthy adult volunteers: A placebo controlled study Indian J Physiol Pharmacol · PMID 26571987 |
Placebo controlled randomised trial |
Healthy adult volunteers (number not in abstract) | Ethanolic leaf extract of Ocimum sanctum in capsules (NOT the essential oil) leaf Not repeated here 30 days · vs Placebo |
Between groups, the leaf extract group improved on several reaction-time and error measures (Sternberg and Stroop). For P300 latency, salivary cortisol and the anxiety inventory, change over time was seen in the extract group only, but the difference between groups was significant for P300 latency alone. No change in heart rate or skin conductance. Several test scores better than placebo Methods, limits and fundingOutcomes: Sternberg and Stroop reaction time and errors, P300 latency, salivary cortisol, State-Trait Anxiety Inventory Limitations: Healthy volunteers, short trial; the sample size is not in the abstract. Leaf extract by mouth; does not describe the oil. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Smith 2002 Safety assessment of allylalkoxybenzene derivatives used as flavouring substances - methyl eugenol and estragole Food Chem Toxicol · PMID 12065208 · DOI |
Expert panel review review |
Rodent data and human exposure estimates for dietary flavouring use | Methyl eugenol and estragole as flavourings n/a Not repeated here n/a · vs n/a |
The FEMA Expert Panel says metabolic activation and covalent binding are dose-dependent and minimal in rodents at roughly 1-10 mg/kg body weight, which it describes as about 100-1000 times anticipated human exposure from flavouring use. Panel opinion Methods, limits and fundingOutcomes: Risk to humans from dietary exposure Limitations: The panel is run by the flavour industry association (FEMA), and the paper is from 2002, before the 2024 IARC classification. It is about food flavouring, not oils used on skin or in air. Funding and conflicts: Industry-linked (Flavor and Extract Manufacturers Association Expert Panel). Read: abstract |
| Such 2026 System-Level, Molecular and Cellular Mechanisms of Selected Plant Adaptogens-A Review Nutrients · PMID 41901106 · DOI |
Narrative review review |
Seven plant adaptogens including Ocimum tenuiflorum | Plant extracts and compounds various Not repeated here n/a · vs n/a |
The review describes lab and animal findings on stress pathways for seven plants including Ocimum tenuiflorum, and says further clinical studies are needed to standardise extracts. It does not single out tulsi oil. Not applicable Methods, limits and fundingOutcomes: Stress-pathway mechanisms Limitations: A mechanisms review covering seven plants; tulsi-specific detail was not in the abstract. Funding and conflicts: The authors declare no conflict of interest. Read: abstract |
| Tangpao 2018 Aromatic Profiles of Essential Oils from Five Commonly Used Thai Basils Foods · PMID 30352978 · DOI |
Laboratory study with a small sniffing panel laboratory |
Oils from two holy basil varieties and three other basils in Thai markets; five semi-trained panellists | Essential oils of white and red holy basil (Ocimum sanctum) and other basils, hydro-distilled from fresh leaves fresh leaf Not repeated here n/a · vs Other basil types |
Estragole, eugenol and methyl eugenol were among the major volatile compounds across the basil types. The oils grouped into an anise-citrus aroma (estragole, geranial, neral) or a spice-like aroma (methyl eugenol, beta-caryophyllene, alpha-cubebene). The panel could tell white from red holy basil oil by how anise-like they smelled. Descriptive only Methods, limits and fundingOutcomes: Chemistry (GC-MS) and described scent Limitations: Five panellists and a small number of samples; the abstract does not say which holy basil group fell in which aroma group. Funding and conflicts: The authors declared no conflict of interest. Read: abstract |
| Vasincu 2025 The Neuroprotective Potential of Ocimum Plant Species: Seasoning the Mind with Sweet and Holy Basil Nutrients · PMID 40944265 · DOI |
Narrative review of experimental studies review |
Lab and animal models of Alzheimer-type disease | Extracts and compounds of Ocimum sanctum and O. basilicum various Not repeated here n/a · vs n/a |
The review says Ocimum extracts raised antioxidant enzymes, lowered lipid peroxidation and reduced beta-amyloid and tau in experiments, and that more research is needed to assess their potential. Not applicable Methods, limits and fundingOutcomes: Antioxidant enzymes, beta-amyloid and tau in models Limitations: Mostly extracts, in cells and animals. Not human evidence, and not specific to the essential oil. Funding and conflicts: No conflict stated in the abstract excerpt read. Read: abstract |
| Vohora 1969 Antifertility screening of plants. 3. Effect of six indigenous plants on early pregnancy in albino rats Indian J Med Res · PMID 5820437 |
Animal study rat |
Albino rats | Aqueous, alcoholic and petroleum-ether extracts of Ocimum sanctum leaves (NOT the essential oil) leaf Not repeated here Early pregnancy · vs Other plants |
The aqueous leaf extract of Ocimum sanctum showed "encouraging results" in the screening; none of the rats that delivered showed teratogenicity up to age 1 month. Not applicable Methods, limits and fundingOutcomes: Anti-fertility and early abortifacient screening Limitations: A 1969 rat screen of leaf extracts. It does not tell us anything about the oil or about women. Funding and conflicts: Not stated. Read: abstract |
| de Groot 2016 Essential Oils, Part IV: Contact Allergy Dermatitis · PMID 27427818 · DOI |
Narrative review review |
Patients with contact allergy to essential oils | Essential oils in general n/a Not repeated here n/a · vs n/a |
Nearly 80 essential oils have caused contact allergy. Of 55 tested in consecutive patients, nine (including clove) gave more than 2% positive patch tests. Most reactions follow pure oils or high-concentration products. Co-reactivity with other oils and the fragrance mix is frequent. Not applicable Methods, limits and fundingOutcomes: Contact allergy Limitations: General review. Tulsi oil is not named in the abstract. Funding and conflicts: Not stated in the abstract. Read: abstract |
| n/a 2026 Poison Control (US National Capital Poison Center): Essential oils: Poisonous when misused (page read 2026-10-25) n/a · Source |
Poison centre education page n/a |
n/a | n/a n/a Not repeated here n/a · vs n/a |
Some essential oils are poisonous if swallowed or absorbed through the skin. Aspirating an oil (it entering the lungs) can cause pneumonia. Children have thin skin and immature livers, which might make them more susceptible. Essential oils may interact with medications. Diluting in a carrier oil is the best way to avoid a bad reaction on skin, and oils should not go on damaged skin. If a rash appears, wash the oil off. Keep oils where children cannot find them. Methods, limits and fundingOutcomes: Safety statements Limitations: General page about essential oils. It does not name tulsi or holy basil, and the page text carries no date. Read: full-text |
| n/a 2026 Pet Poison Helpline: Essential Oils (page read 2026-10-25) n/a · Source |
Veterinary poison helpline page n/a |
n/a | n/a n/a Not repeated here n/a · vs n/a |
Essential oil poisoning can affect all species, but cats and birds are at the greatest risk. Common signs include drooling, vomiting, lethargy, loss of appetite and breathing or skin signs. Methods, limits and fundingOutcomes: Safety statements Limitations: General page. It does not name tulsi or holy basil, which is not proof the oil is safe for pets. Read: full-text |
| n/a 2026 US Food and Drug Administration: Aromatherapy (page read 2026-10-25) n/a · Source |
Regulator / government health page n/a |
n/a | n/a n/a Not repeated here n/a · vs n/a |
How an aromatherapy product is regulated depends mainly on its intended use. The law does not require cosmetics to have FDA approval before they are sold. A product with drug claims is regulated as a drug even if it comes from a plant. Methods, limits and fundingOutcomes: Safety statements Limitations: Regulatory overview, not a safety assessment of any oil. Tulsi is not named. Read: full-text |
| n/a 2026 GBIF Backbone Taxonomy: Ocimum tenuiflorum L. (match API read 2026-10-25) n/a · Source |
Registry or database n/a |
n/a | n/a n/a Not repeated here n/a · vs n/a |
Ocimum tenuiflorum L. is the ACCEPTED species name (species key 2927100, family Lamiaceae). Ocimum sanctum L. (key 2927101) is a SYNONYM that points to it. Methods, limits and fundingOutcomes: Accepted name and synonym Limitations: Registry check only. Read: full-text |
| n/a 2026 PubChem compound records: eugenol (CID 3314), methyleugenol (CID 7127), beta-caryophyllene (CID 5281515), read 2026-10-25 n/a · Source |
Registry or database n/a |
n/a | n/a n/a Not repeated here n/a · vs n/a |
Eugenol: CID 3314, C10H12O2, 2-methoxy-4-prop-2-enylphenol. Methyleugenol: CID 7127, C11H14O2, 1,2-dimethoxy-4-prop-2-enylbenzene. Beta-caryophyllene: CID 5281515, C15H24. Methods, limits and fundingOutcomes: Compound identity Limitations: Identity only. trans-beta-elemene was not looked up. Read: full-text |
What we do not know yet
- What the evidence supports: for the oil, very-low at best (one small dental trial); everything else is lab work or leaf extract.
- No trial of tulsi oil as a scent or on the skin was found.
- No patch-test rate, asthma, epilepsy or sun-sensitivity data for tulsi oil were found.
- No study of tulsi oil in pregnancy, breastfeeding or pets, and no poisoning case report.
- No LiverTox, LactMed, IFRA, SCCS, EMA or NCCIH statement for tulsi 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 4
Bacterial counts (CFU) in the root canal
Decrease in trials
Colony-forming units counted from samples taken from the tooth canal, aerobic and anaerobic.
Very low certaintyResults and what it means
Why it was measured
Main outcome of the children's dental trial.
Statistical vs. clinical meaning
A lab count of bacteria, not tooth health or pain.
Safety implication
A lower count does not show the oil is safe for home use.
| Study | Result | People | Product |
|---|---|---|---|
| 1 | Counts fell significantly after the tulsi-oil dressing; the antibiotic paste did better, and saline rinsing also lowered counts. |
Mosquito landing and feeding (repellency test)
Decrease in trials
Whether mosquitoes land or feed on a treated surface over 6 hours.
Not enough evidenceResults and what it means
Why it was measured
Main outcome of the repellency screening.
Statistical vs. clinical meaning
A screening result, not proof of protection from bites or disease.
Safety implication
Says nothing about skin reactions.
| Study | Result | People | Product |
|---|---|---|---|
| 11 | No landing up to 6 hours with 20% tulsi leaf oil in ethanol, comparable to 20% DEET. |
Interferon-gamma, interleukin-4, T-helper and NK cells (leaf extract trial)
Increase in trials
Immune signal proteins and cell percentages measured in blood samples.
Very low certaintyResults and what it means
Why it was measured
Main outcomes of the leaf extract trial.
Statistical vs. clinical meaning
Lab markers; a rise is not the same as better health.
Safety implication
Leaf extract only; says nothing about the oil.
| Study | Result | People | Product |
|---|---|---|---|
| 14 | Higher after 4 weeks on tulsi leaf extract than placebo: IFN-gamma p=0.039, IL-4 p=0.001, T-helper cells p=0.001, NK cells p=0.017. |
Reaction time and error rate on thinking tests, P300 latency (leaf extract trial)
Improve in trials
Timed computer tests (Sternberg, Stroop) and a brain-wave timing measure.
Very low certaintyResults and what it means
Why it was measured
Main outcomes of the leaf extract cognition trial.
Statistical vs. clinical meaning
Test performance in healthy people, not a treatment effect.
Safety implication
Leaf extract only; says nothing about the oil.
| Study | Result | People | Product |
|---|---|---|---|
| 18 | Better than placebo on several reaction-time and error measures; for P300 latency the difference from placebo was also significant. Cortisol and anxiety scores did not differ significantly from placebo. |
Safety
What studies and official sources say about side effects, medicines and who should check first. Each point shows what kind of evidence it comes from.
Main points to know 6
- Do not swallow tulsi oil. It is rich in eugenol or methyl eugenol, and eugenol overdose has caused severe liver injury.. Tulsi oil is made of different compounds depending on the plant: eugenol-rich (about 32% to 35%) in a Nepal study, or methyl eugenol-rich (72.5% and 92.4% in Indian papers). LiverTox says eugenol in therapeutic doses has not been linked to clinically apparent liver injury, but high-dose ingestion can cause severe liver injury. A 15-month-old boy developed liver failure after swallowing 10 ml of clove oil, an eugenol-rich oil. We found no tulsi-oil poisoning case. Authoritative guidance 13 7 16 8 17 25
- Methyl eugenol is classed as probably carcinogenic to humans by IARC (2024), and some tulsi oils are mostly methyl eugenol.. IARC concluded in 2024 that methyleugenol is probably carcinogenic to humans (Group 2A). In the US government's animal studies it increased liver tumours in mice and caused tumours in rats at large doses given by stomach tube. A 2002 flavour-industry panel argued that the risk at ordinary dietary levels is very low. Nobody has measured the risk from smelling or skin use of tulsi oil, and we found no such figure. Methyl eugenol content depends on the chemotype, so labels matter. Authoritative guidance 5 15 19 8 17
- Skin: eugenol is a known skin sensitiser, and no patch-test rate exists for tulsi oil.. In a mouse sensitisation test eugenol gave an EC3 of 5.4%, and the authors say oils are generally about as potent as their main compound. A review says nearly 80 essential oils have caused contact allergy, including clove, an eugenol-rich oil, and that most reactions follow pure oils or high-concentration products. Poison Control advises diluting oils in a carrier oil, not using them on damaged skin, and washing off if a rash appears. This page gives no dilution. Authoritative guidance 10 24 4 25
- Children and pets: keep the bottle locked away.. Poison Control says children have thin skin and immature livers and may be more susceptible to toxic effects. Pet Poison Helpline says cats and birds are at greatest risk of essential-oil poisoning. Neither page names tulsi, which is not proof it is safe. Authoritative guidance 25 26
- Pregnancy and breastfeeding: not shown to be safe.. A 1999 review says safety of aromatherapy oils in pregnancy has not been clearly demonstrated. A 1969 rat study of tulsi LEAF extract found encouraging results in an anti-fertility and early-abortion screen; this is animal work on a leaf extract, not the oil, but it is one more reason to ask a midwife or doctor. We found no data on the oil in pregnancy or breastfeeding. Narrative review 12 23
- Eugenol may thin the blood in lab studies; the effect of tulsi oil in people is unknown.. In donor platelets and mice, eugenol blocked platelet activation. This is purified eugenol, in the lab. If you take blood thinners or have surgery planned, tell your doctor or pharmacist about any essential oils you use. Laboratory 2
Side effects 5
| Effect | How often | Severity and recovery | Evidence |
|---|---|---|---|
| Skin irritation and allergic skin reaction (contact dermatitis) Based on eugenol and on essential oils in general. In the IVDK database of 10,930 patients, 8.3% reacted to at least one of 12 oils tested; tulsi was not named in the part of the abstract read. | No rate found for tulsi oil | Not graded for tulsi oil Usually settles when exposure stops (Poison Control says wash off); the allergy itself can last. | Authoritative guidance 10 24 4 25 |
| Liver injury if swallowed (eugenol) From clove oil and eugenol. Tulsi oil is eugenol-rich in some samples and methyl eugenol-rich in others; no tulsi-oil liver case was found. | Not known for tulsi oil | Severe (fulminant liver failure) in one clove-oil case Resolved with hospital treatment in the clove-oil case | Case report 7 13 |
| Poisoning if swallowed, and lung injury if the oil is breathed into the lungs General Poison Control warning about essential oils, including pneumonia if oil enters the lungs. | Not known for tulsi oil | Can be serious Not given | Authoritative guidance 25 |
| Cancer hazard of methyl eugenol IARC Group 2A for methyleugenol. The classification is about the compound and its hazard, not about occasional scent or skin use of an oil. | No exposure risk figure for tulsi oil | Hazard classification only Not applicable | Authoritative guidance 5 15 |
| Harm to cats, dogs and birds Pet Poison Helpline says cats and birds are at greatest risk of essential-oil poisoning. | Not known for tulsi oil | Can be serious Not given | Authoritative guidance 26 |
Liver
Eugenol in therapeutic doses has not been implicated in clinically apparent liver injury, but high-dose ingestion can cause severe liver injury (LiverTox). A toddler developed fulminant liver failure after swallowing 10 ml of clove oil, an eugenol-rich oil. In animal studies, methyleugenol raised liver injury markers at higher doses and caused liver tumours in mice. We found no case of liver injury from tulsi oil and no LiverTox record for it. 13 7 15
How often. Not established for tulsi oil.
Monitoring. Not applicable. Do not swallow essential oils.
- . 7
This is a safety connection. It is not evidence that Tulsi (Holy Basil) Oil supports liver health.
Medicines and supplements 3
| With | Why it matters | Importance | Evidence | What to do |
|---|---|---|---|---|
| Warfarin, aspirin, clopidogrel and similar medicines blood thinners and antiplatelet medicines | Purified eugenol blocked platelet activation in donor platelets and mice. | Not shown for tulsi oil in people. | Laboratory Very low certainty 2 | If you use blood thinners, ask a pharmacist before using essential oils. |
| Clove oil, cinnamon oil, fragrances containing eugenol or isoeugenol allergy | Co-reactivity among essential oils and with the fragrance mix is described as frequent, partly from shared ingredients. | If you have reacted to an eugenol-containing product you may react to tulsi oil. Not tested for tulsi oil. | Narrative review Low certainty 24 10 | Tell a pharmacist or dermatologist about earlier reactions. |
| Prescription and over-the-counter medicines in general general medicine interactions | Poison Control says essential oils may interact with medications. | General statement; no tulsi-oil interaction was found in the sources read. | Authoritative guidance Not enough evidence 25 | Ask a pharmacist. |
Who should check first 6
| Situation | Advice | Evidence |
|---|---|---|
| Swallowing tulsi oil or any essential oil | Do not swallow. If a child or pet may have swallowed any essential oil, call poison control (US 1-800-222-1222) or your emergency number. | Authoritative guidance 25 13 7 |
| Known allergy to clove, cinnamon, fragrance mix, or any essential oil | Avoid. Cross-reactions are described among eugenol-containing products and essential oils. | Narrative review 24 10 |
| Undiluted oil on the skin or damaged skin | Avoid. Poison Control says to dilute in a carrier oil and not use on damaged skin; this page gives no dilution. | Authoritative guidance 25 24 |
| Pregnancy, breastfeeding, babies and young children | Ask a doctor or midwife first; safety is not shown. | Narrative review 12 25 |
| Homes with cats or birds | Ask a vet before diffusing or storing any essential oil within reach. | Authoritative guidance 26 |
| Taking blood thinners, or planned surgery | Tell your doctor or pharmacist about any essential oil use. | Laboratory 2 |
Overdose, product quality and regulators
Summary. No lethal or toxic amount for tulsi oil is given in the sources we read, and none is given here.
Amounts. No safe amount is established, and this page gives none.
Onset and course. Not described for tulsi oil. In the clove-oil case, ALT was above 13,000 U/L at 24 hours.
Repeated use. Repeated skin exposure is the route linked to allergy for essential oils in general.
Animal data. Methyleugenol caused liver tumours in mice and several tumour types in rats in 2-year stomach-tube studies (NTP).
Toxic parts. The oil is a concentrate. Eugenol and methyl eugenol are the compounds of concern, and their share depends on the plant (eugenol 32-35% in a Nepal oil; methyl eugenol 72.5% and 92.4% in Indian papers).
Not read. Full IFRA and EU cosmetic allergen listings, Tisserand safety data, the full NTP and IARC reports, LiverTox for tulsi, EMA/HMPC and FDA statements on tulsi oil were not opened.
What is in a bottle can differ from the label, and tulsi oil varies a lot between plants and harvests.
Unknown species, strength and contaminants. Poison Control says essential-oil products are not well regulated and that it can be hard to know what is in a bottle. 25
Composition varies. One tulsi oil was about a third eugenol with beta-elemene and beta-caryophyllene; others were 72.5% and 92.4% methyl eugenol. Harvest method changed the methyl eugenol content in another paper. 16 8 17 9
Other basils. Sweet basil (Ocimum basilicum) oil is mostly methyl chavicol and linalool, so it is a different oil. 16
Regulation. The FDA says cosmetics do not need approval before sale and that the law treats a product by its intended use, so a plant origin does not exempt a product with drug claims. 27
| Body | Action | Date |
|---|---|---|
| International Agency for Research on Cancer (IARC / WHO) (International) | 2024: methyleugenol probably carcinogenic to humans (Group 2A); occurs naturally in essential oils; flavouring use is prohibited in the EU and USA. source | 2024 |
| LiverTox (NIDDK, US NIH) (United States) | Eugenol in therapeutic doses not implicated in clinically apparent liver injury; ingestion of high doses can cause severe liver injury. source | 2019-10-28 |
| Poison Control (National Capital Poison Center) (United States) | General warnings on essential oils: poisoning if swallowed or absorbed, pneumonia if aspirated, dilute for skin, children more susceptible. source | 2026-10-25 |
| Pet Poison Helpline (United States) | Essential oil toxicosis can affect all species; cats and birds are at greatest risk. source | 2026-10-25 |
| US Food and Drug Administration (FDA) (United States) | Aromatherapy products are regulated by intended use; cosmetics need no pre-market approval. source | 2026-10-25 |
| European Food Safety Authority (EFSA) (European Union) | 2023 opinion on clove oils (up to 0.13% methyleugenol): treat as skin, eye and respiratory irritant and skin sensitiser; minimise handler exposure to methyleugenol. Not about tulsi oil. source | 2023-07 |
When to get medical help
- If a child or pet may have swallowed any essential oil, call poison control (US: 1-800-222-1222) or your emergency number now.
- Choking, coughing or trouble breathing after oil may have entered the lungs.
- Swelling of the face or throat, trouble breathing, or a spreading rash after contact with any essential oil.
- Vomiting, unusual sleepiness, yellow skin or eyes, or dark urine after swallowing any essential oil.
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 tulsi oil safe to swallow?
No. Do not swallow essential oil. Poison Control warns some oils are poisonous if swallowed, and eugenol, a main compound in some tulsi oils, caused liver failure in a toddler who swallowed clove oil. If a child or pet may have swallowed any essential oil, call poison control (US: 1-800-222-1222) or your emergency number.
Is tulsi oil the same as tulsi tea or tulsi capsules?
What are eugenol and methyl eugenol, and why do they matter?
They are natural compounds that make up much of some tulsi oils: eugenol about a third of a Nepal oil, methyl eugenol 72.5% and 92.4% in Indian papers. High-dose swallowed eugenol can injure the liver (LiverTox), and IARC classes methyl eugenol as probably carcinogenic to humans. Neither is a measured risk from smelling the oil.
Can tulsi oil cause skin allergy?
Does tulsi oil reduce stress or help immunity?
Is there any human trial of tulsi oil?
One. In 40 children, a tulsi-oil dressing placed in baby-tooth root canals by a dentist lowered bacterial counts, but an antibiotic paste did better. It is a dental use and does not support use at home.
Does tulsi oil repel mosquitoes?
In one lab screening test, 20% tulsi leaf oil in ethanol stopped Aedes aegypti landing for up to 6 hours, like 20% DEET. That test did not look at skin reactions or real-life protection, so it is not advice to use the oil on skin.
Is tulsi oil safe in pregnancy or breastfeeding?
Is tulsi oil safe for children?
Ask a children's doctor first. Poison Control says children have thin skin and immature livers and may be more susceptible. Keep bottles out of reach.
Is tulsi oil safe for cats, dogs and birds?
Unknown. Pet Poison Helpline says cats and birds are at greatest risk from essential oils and does not name tulsi, which is not proof it is safe. Ask a vet.
Does tulsi oil interact with medicines?
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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 24 PubMed records, the Poison Control, Pet Poison Helpline and FDA pages, and checked the plant name in GBIF and three compounds in PubChem. We did not find or read a LiverTox, LactMed, IFRA or EMA statement for tulsi oil.
- 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. Industry links are labelled where the abstract showed them.
Sources 29
Each source was opened and checked. Where we read only the abstract, it says so. The small numbers in the text point here.
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- EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP). Safety and efficacy of feed additives consisting of essential oils derived from the flower buds or the leaves of Syzygium aromaticum (clove bud oil and clove leaf oils) for all animal species. EFSA Journal. 2023. PMID 37522096. DOI 10.2903/j.efsa.2023.8183. (abstract)
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- IARC Working Group on the Identification of Carcinogenic Hazards to Humans. Aspartame, Methyleugenol, and Isoeugenol (IARC Monographs volume). IARC Monographs. 2024. PMID 39715313. (abstract)
- Jamshidi N, Cohen MM. The Clinical Efficacy and Safety of Tulsi in Humans: A Systematic Review of the Literature. Evid Based Complement Alternat Med. 2017. PMID 28400848. DOI 10.1155/2017/9217567. (abstract)
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- LiverTox, NIDDK. Eugenol (Clove Oil). LiverTox: Clinical and Research Information on Drug-Induced Liver Injury. LiverTox (NIDDK), record updated 2019. 2012. PMID 31869191. (abstract)
- Mondal S, Varma S, Bamola VD, et al. Double-blinded randomized controlled trial for immunomodulatory effects of Tulsi (Ocimum sanctum Linn.) leaf extract on healthy volunteers. J Ethnopharmacol. 2011. PMID 21619917. DOI 10.1016/j.jep.2011.05.012. (abstract)
- National Toxicology Program. NTP Toxicology and Carcinogenesis Studies of Methyleugenol (CAS NO. 93-15-2) in F344/N Rats and B6C3F1 Mice (Gavage Studies). Natl Toxicol Program Tech Rep Ser. 2000. PMID 12563349. (abstract)
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- Sampath S, Mahapatra SC, Padhi MM, et al. Holy basil (Ocimum sanctum Linn.) leaf extract enhances specific cognitive parameters in healthy adult volunteers: A placebo controlled study. Indian J Physiol Pharmacol. 2015. PMID 26571987. (abstract)
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- n/a. Poison Control (US National Capital Poison Center): Essential oils: Poisonous when misused (page read 2026-10-25). n/a. 2026. (full-text)
- n/a. Pet Poison Helpline: Essential Oils (page read 2026-10-25). n/a. 2026. (full-text)
- n/a. US Food and Drug Administration: Aromatherapy (page read 2026-10-25). n/a. 2026. (full-text)
- n/a. GBIF Backbone Taxonomy: Ocimum tenuiflorum L. (match API read 2026-10-25). n/a. 2026. (full-text)
- n/a. PubChem compound records: eugenol (CID 3314), methyleugenol (CID 7127), beta-caryophyllene (CID 5281515), read 2026-10-25. n/a. 2026. (full-text)