Essential Oils & Aromatherapy · Essential oil
Bay Oil
Pimenta racemosa (West Indian bay) and Laurus nobilis (bay laurel) · also called Bay leaf oil, bay rum tree oil, laurel leaf oil, Pimenta oil
Bay oil is sold under one name but comes from two different plants. West Indian bay oil is mostly eugenol, the same main compound as clove oil. Bay laurel oil is mostly 1,8-cineole and also holds some methyl-eugenol. Almost all the research is lab work. One short scent study reported lower blood pressure with bay laurel. The main cautions: laurel oil is a documented skin allergen, eugenol-rich oil can injure the liver if swallowed, and children and pets should be kept away.
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 Bay Oil
Bay oil means two different oils. West Indian bay (Pimenta racemosa) oil is mostly eugenol. Bay laurel (Laurus nobilis) oil is led by 1,8-cineole with some methyl-eugenol. Safety comes first: laurel oil is a documented skin allergen, eugenol is a known skin sensitiser, eugenol-rich oil can injure the liver if swallowed, and children and pets should be kept away. Human research is one very-low-certainty scent study.
What bay oil is
West Indian bay is Pimenta racemosa (Mill.) J.W.Moore, in the myrtle family (Myrtaceae). Bay laurel is Laurus nobilis L., in the laurel family (Lauraceae). GBIF lists both as accepted names. A 2025 paper says Pimenta racemosa is native to Venezuela, Puerto Rico and Jamaica.
The oils in the studies were distilled from leaves (and, for West Indian bay, stems in one study). Their chemistry differs. West Indian bay oil was mainly eugenol, then myrcene and limonene in one leaf oil. Laurel oil was led by 1,8-cineole, with methyl-eugenol, alpha-terpinyl acetate and linalool.
The dried bay leaf used in cooking, laurel leaf tea, clove oil and pure eugenol are different products. Findings for one do not carry over to another.
What people use it for, and how strong the evidence is
Human evidence is thin. One short study in Crimea tested oil vapours in 849 women with high blood pressure and reported lower blood pressure with bay laurel oil. Its abstract gives no numbers, so certainty is very low. No study of West Indian bay oil in people was found.
Everything else is lab, computer or animal work: stomach bacteria in a dish, antioxidant and enzyme tests, a mouse memory study and a tick test. The authors of these papers call their results promising and ask for further studies, but none tested people.
Laurel oil is also used in massage, according to a case report. We found no trial of either oil for pain, skin, hair or scalp, which are the common product claims.
The research in one view
One controlled scent study, abstract only, no numbers. Two animal studies of dried leaf or an oil mixture in feed exist but are not about the oils on this page. Lab papers mostly measure what is in the oil and what it does in a test tube.
No trial of either oil on skin, hair or by swallowing was found. Do not read a lab result as a health benefit.
What regulators say
In the US, 'bay leaves' (Laurus nobilis) and 'bay (myrcia oil)' (Pimenta racemosa) are on the FDA's list of essential oils generally recognised as safe for use as food additives. That is a food-flavouring rule. It is not a finding about aromatherapy, skin use or swallowing bottled oil.
The FDA says a product sold with claims to treat disease or ease pain is a drug, while one meant only to smell good is a cosmetic that needs no approval before sale. We did not read European (EMA, EFSA, SCCS) or fragrance-industry (IFRA) statements on bay oil.
At a glance
Traditional uses history, not proof
- West Indian bay (Pimenta racemosa) is called a spice used in traditional medicine for several ailments (2022 paper).
- Laurel leaf infusion or decoction is used in Italian folk medicine for gut complaints and gas (2024 paper).
- Laurus nobilis is used in traditional Tunisian medicine for rheumatism and some nerve complaints (2024 paper).
- Laurus nobilis oil is widely used in massage therapy (2015 case report).
- Both oils are on the US list of essential oils generally recognised as safe as food flavourings (FDA).
Studied for research
- Blood pressure after breathing bay laurel vapour, very-low
- Memory in mice, bay laurel oil, insufficient
- Stomach bacteria in a dish, West Indian bay oil, insufficient
- Antioxidant and enzyme tests, both oils, lab only, insufficient
- Killing ticks in the lab, West Indian bay oil, insufficient
Main compounds
- Eugenol (main compound of West Indian bay oil)
- 1,8-Cineole (main compound of bay laurel oil)
- Methyl-eugenol (in bay laurel oil)
- Myrcene, limonene, linalool, alpha-terpinyl acetate
Common forms
- Essential oil from West Indian bay leaves
- Essential oil from bay laurel leaves
- Diluted massage and hair products (contents vary)
- Dried bay leaf (kitchen spice, a different product)
- Laurel leaf infusion (a different product)
Research links: Poison Control: Essential oils · Pet Poison Helpline: Essential oils · FDA: Aromatherapy · LiverTox: Eugenol (clove oil) · Essential oils and contact allergy (review abstract) · Blood pressure and oil vapours (abstract) · Eugenol patch-test study (abstract) · Research Library · Genes & Biomarkers Library
What it is and its history
- Accepted scientific name
- Two plants: Pimenta racemosa (West Indian bay) and Laurus nobilis (bay laurel)
- Naming authority
- Pimenta racemosa (Mill.) J.W.Moore; Laurus nobilis L.
- Common names
- West Indian bay (English); Bay rum tree (English); Bay laurel (English); Sweet bay (English); Laurel (English); Bay leaf oil (English); Pimenta oil (English)
- Family or group
- Myrtle family (Myrtaceae) for West Indian bay; laurel family (Lauraceae) for bay laurel, per GBIF.
- Classification
- Plantae > Myrtaceae (Pimenta racemosa) and Lauraceae (Laurus nobilis) > Pimenta and Laurus > Pimenta racemosa; Laurus nobilis
- Native range
- A 2025 paper says Pimenta racemosa is native to Venezuela, Puerto Rico and Jamaica. The native range of Laurus nobilis was not checked.
- Habitat
- Not checked.
- What it looks like
- Part used: The lab studies read used leaves (and in one study stems) of Pimenta racemosa, and leaves of Laurus nobilis.
- Look-alikes and adulterants
- Other oils are sold as 'bay': this page is about West Indian bay and bay laurel only. Clove oil is also rich in eugenol but is a different plant (Eugenia caryophyllata, per one tick study). A 1974 PubMed record is titled 'California bay oil'; we read only its title and do not use it.
Traditional use and history history, not clinical proof
| Tradition or era | Documented use | Source |
|---|---|---|
| Traditional medicine, West Indian bay | A 2022 paper calls Pimenta racemosa a commonly known spice used in traditional medicine to treat several ailments, without naming them. | Ayoub 2022 |
| Folk medicine, bay laurel (Italy) | A 2024 paper says laurel is commonly used in folk medicine as an infusion or decoction for gut diseases and flatulence, as a carminative, antiseptic and anti-inflammatory. | Fantasma 2024 |
| Traditional Tunisian medicine, bay laurel | A 2024 paper says laurel has been widely used in traditional Tunisian medicine for rheumatism and some neurological disorders. | Smach 2024 |
| Massage therapy | A 2015 case report says Laurus nobilis essential oil is widely used in massage therapy for anti-inflammatory and pain-relieving effects. | Uzuncakmak 2015 |
| Today (food use) | Both bay oils are on the US list of essential oils generally recognised as safe for use as food flavourings. | US FDA 21 CFR 182.20 |
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 | phenylpropanoid (phenol) | Pimenta racemosa leaf and stem oil; small amounts in Laurus nobilis leaf oil 57.84% (leaf) and 59.76% (stem) in one study; 70.87% in an Egyptian leaf oil; 64.07% in a tick study oil; 1.97% to 4.12% in Italian laurel oils. | A known skin sensitiser. High-dose ingestion can injure the liver (LiverTox, clove oil). Antioxidant in lab tests. 25 1 5 7 6 12 10 | Lab and human skin and case data |
| 1,8-Cineole (eucalyptol) PubChem 2758 | monoterpene ether | Laurus nobilis leaf oil 43.52% to 31.31% in seven Italian laurel oils. | The main compound of the laurel oils analysed. Docked to acetylcholinesterase in computer work (mouse paper). 26 6 15 | Composition and computer work |
| Methyleugenol PubChem 7127 | phenylpropanoid (alkenylbenzene) | Laurus nobilis leaf oil 14.96% to 4.07% in seven Italian laurel oils. Not given for West Indian bay. | Described as genotoxic and carcinogenic in rodents (2025 paper and 2023 review). No human risk figure for laurel oil was found. 27 6 8 4 | Laboratory and animal |
| Other main compounds | monoterpenes and esters | Both oils West Indian bay: beta-myrcene 12.88%, D-limonene 8.35% (one Egyptian leaf oil). Laurel: alpha-terpinyl acetate 13.00% to 8.51%, linalool 11.72% to 1.08%, sabinene, alpha-pinene, terpinen-4-ol. | Composition only; no separate activity read. 5 6 | Composition only |
Mechanisms, receptors and pathways
| Target or pathway | Gene or receptor | What was found | Level |
|---|---|---|---|
| Cholinesterase enzymes (acetylcholinesterase, butyrylcholinesterase) | AChE, BChE | West Indian bay leaf oil blocked both enzymes in test tubes; computer docking suggested laurel compounds bind acetylcholinesterase. Proposals, not shown in people. 5 15 | Lab and computer |
| Soluble epoxide hydrolase (sEH) | sEH | Laurel oils blocked this inflammation-related enzyme in the lab and in computer models. 6 | Lab and computer |
| Skin sensitisation by eugenol | immune (contact allergy) | Lab work on reconstructed skin suggests eugenol forms radicals and reactive forms that bind skin proteins; human patch tests show positive reactions at very low concentrations. 14 12 | Lab and human observational |
| Eugenol and the liver | not applicable | High-dose swallowed eugenol can cause severe liver injury; N-acetylcysteine was given in the toddler case. 9 10 | Case report and database entry |
Absorption, metabolism and elimination
- Absorption
- Not described in any source read for bay oil.
- Distribution
- Not established.
- Metabolism
- Not described for bay oil.
- Elimination
- Not established.
- Bioavailability
- Not established.
Isolated compounds versus whole extracts
West Indian bay oil, bay laurel oil, dried bay leaf (the kitchen spice), laurel leaf infusion, clove oil and pure eugenol are different things. Findings for one do not carry over to another. The rabbit and quail feed studies found used dried leaf or an oil mixture, not the oils on this page.
Nutritional composition
Bay oils are not nutrients. Both are on the US food-flavouring list.
1 very low certainty4 not enough evidence
What is Bay Oil good for?
The uses people ask about and how strong the evidence is for each. Read the certainty label first. There is one human study, with no numbers in its abstract. Everything else is lab, computer or animal work and does not show a benefit in people.
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.
Blood pressure after breathing bay laurel oil vapour (Laurus nobilis, women with hypertension)
Very low certaintyOne short study in Crimea tested the vapour of about 23 plant oils on 849 women with high blood pressure. It reported that bay laurel oil lowered blood pressure after 10 and after 20 minutes compared with a control group that only did a relaxation session. The abstract gives no numbers, so we cannot say by how much. No study of West Indian bay oil was found.
1 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
A controlled inhalation study in 849 women aged 55 to 89 with high blood pressure. Two series (10 and 20 minutes). Control groups did a relaxation session. Test groups did the same session while breathing the vapour of one oil (1 mg per cubic metre of air). Blood pressure and heart rate were measured before and after.
Results
Bay laurel oil showed an antihypertensive effect at both 10 and 20 minutes. Clove tree oil worked at 10 minutes only. Lavender, peppermint, fennel and several other oils showed no effect. The abstract gives no blood-pressure values or p-values.
Effect sizes as reported
Not given in the abstract.
Why this rating
One study, only the abstract was read, no numbers, a single short session, and no repeat by other groups. The oils were tested one at a time against a relaxation-only control, but how well the groups were matched is not stated.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Women aged 55 to 89 with hypertension in Crimea. Not tested in men, children or pregnancy.
Limits
No numbers in the abstract. Short single exposure. Funding not stated. Lasting benefit is unknown. Bay laurel and not West Indian bay was named.
Why researchers looked
People look for gentle, low-risk add-ons for high blood pressure, and smelling an oil seems low risk.
Traditional use
A 2024 paper says laurel leaf infusion or decoction is used in folk medicine for gut complaints and gas. That is a leaf drink, not the oil.
Proposed mechanism Preliminary mechanism
Not established. The abstract proposes none for this oil.
A proposed mechanism does not show that the effect happens in people.
Not a replacement for blood-pressure medicine. Scent only: this does not support swallowing the oil or putting it on skin undiluted.
Memory in mice (Laurus nobilis oil, mouse study)
Not enough evidenceIn mice given a drug that impairs memory, bay laurel oil at 100 mg per kg improved maze performance and lowered signs of oxidative damage in the brain. This is mouse work with a dose given to the animals (the abstract does not say how), not a smell. It does not show a memory benefit in people.
1 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
None found.
Results
Treated mice did better in the Morris water maze and Y maze than mice given scopolamine alone (p < 0.05), with less oxidative damage.
Effect sizes as reported
p < 0.05 versus the scopolamine group.
Why this rating
Mouse work only. A mouse dose does not transfer to a person. No human trial of bay oil for memory was found.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Mice.
Limits
Animal study; route of giving not shown in the abstract; no human data.
Why researchers looked
Researchers look for plant oils that affect brain enzymes linked to memory.
Traditional use
The paper says laurel is used in traditional Tunisian medicine for rheumatism and some nerve complaints.
Proposed mechanism Preliminary mechanism
The authors suggest the oil changes cholinergic activity and acts as an antioxidant. Computer docking suggested 1,8-cineole and alpha-terpinyl acetate bind acetylcholinesterase. These are proposals.
A proposed mechanism does not show that the effect happens in people.
Mouse study only. Do not swallow bay oil.
Stomach bacteria in a dish (Pimenta racemosa stem and leaf oil, lab)
Not enough evidenceIn a test tube, West Indian bay stem oil stopped Helicobacter pylori growth at 3.9 microgram per mL. The antibiotic clarithromycin did it at 1.95 in the same test. This is bacteria in a dish and says nothing about people.
1 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
None found.
Results
Stem oil (eugenol 59.76%) stopped bacterial growth at 3.9 microgram per mL; clarithromycin at 1.95. Leaf oil was 57.84% eugenol.
Effect sizes as reported
MIC 3.9 versus 1.95 microgram per mL.
Why this rating
Bacteria in a dish and computer docking only. Oil dissolved in a test tube is not the same as oil swallowed, which carries liver risks (see Safety).
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
None (bacteria).
Limits
Lab only. Not tested in animals or people.
Why researchers looked
Researchers look for natural compounds that stop the stomach bacterium that causes ulcers.
Traditional use
The paper calls Pimenta racemosa a spice used in traditional medicine for several ailments, without detail.
Proposed mechanism Preliminary mechanism
Computer models suggested decanal, eugenol, terpineol, delta-cadinene and amyl vinyl could bind H. pylori urease. A proposal from computer work.
A proposed mechanism does not show that the effect happens in people.
Test-tube work. Not a treatment for stomach infection; see a doctor.
Antioxidant and enzyme-blocking tests (Pimenta racemosa leaf oil and Laurus nobilis leaf oil, lab)
Not enough evidenceBoth oils scored well in chemical antioxidant tests and blocked several enzymes in test tubes. Authors speculate about uses for Alzheimer's, diabetes and skin pigmentation, but they ran no animal or human tests and call for them.
2 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
None found.
Results
West Indian bay leaf oil from Egypt: eugenol 70.87%, beta-myrcene 12.88%, D-limonene 8.35%, high antioxidant scores and enzyme-blocking activity. Italian laurel leaf oils: mainly 1,8-cineole, with methyl-eugenol, alpha-terpinyl acetate and linalool, antioxidant activity and sEH blocking in the lab and in computer models.
Effect sizes as reported
Chemical assay values only.
Why this rating
Test-tube and computer results. They do not show benefit in people.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
None.
Limits
Chemical assays; no animal or human data in these papers.
Why researchers looked
Eugenol and cineole-rich oils are common in plant-oil screening work.
Traditional use
Laurel leaf infusions and decoctions are used in folk medicine for gut complaints and gas (abstract of a 2024 paper). That is a leaf drink, not the oil.
Proposed mechanism Preliminary mechanism
Enzyme blocking in test tubes: acetylcholinesterase, butyrylcholinesterase, tyrosinase, alpha-glucosidase (West Indian bay); soluble epoxide hydrolase, in the lab and in computer docking (laurel). Proposals, not shown to matter in the body.
A proposed mechanism does not show that the effect happens in people.
Chemical tests only.
Killing ticks in the lab (Pimenta racemosa oil)
Not enough evidenceWest Indian bay oil, mostly eugenol, killed tick larvae, nymphs and adults in a laboratory test. Clove oil and eugenol did too. It was not tested as a repellent on people or pets, and it is not an evidence-based tick protection.
1 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
None found.
Results
Bay oil (eugenol 64.07%) killed unfed Asian longhorned tick larvae (LC50 1.20 mg per mL), nymphs (1.65) and adults (0.51).
Effect sizes as reported
LC50 1.20, 1.65 and 0.51 mg per mL.
Why this rating
Ticks in a lab. Nothing on use on skin, clothes, pets or yards, or on safety of such use.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Ticks.
Limits
Contact test on ticks; eugenol is a known skin sensitiser (see Safety).
Why researchers looked
Ticks spread disease and researchers look for alternatives to chemical acaricides.
Traditional use
Not described in the abstract.
Proposed mechanism Preliminary mechanism
In this study the oils did not change acetylcholinesterase; clove oil and eugenol blocked carboxylesterase. The mechanism for bay oil is not established.
A proposed mechanism does not show that the effect happens in people.
A lab test on ticks, not a skin product test.
Connections to the rest of health
How Bay 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 |
|---|---|---|---|---|
| Blood Pressure Support | Very low certainty | Blood pressure after breathing bay laurel oil vapour (Laurus nobilis, women with hypertension): One short study in Crimea tested the vapour of about 23 plant oils on 849 women with high blood pressure. It reported that bay laurel oil lowered blood pressure after 10 and after 20 minutes compared with a control group that only did a relaxation session. The abstract gives no numbers, so we cannot say by how much. No study of West Indian bay oil was found. | 17 | |
| Memory Support | Not enough evidence | Memory in mice (Laurus nobilis oil, mouse study): In mice given a drug that impairs memory, bay laurel oil at 100 mg per kg improved maze performance and lowered signs of oxidative damage in the brain. This is mouse work with a dose given to the animals (the abstract does not say how), not a smell. It does not show a memory benefit in people. | 15 | |
| Brain Health | Not enough evidence | Memory in mice (Laurus nobilis oil, mouse study): In mice given a drug that impairs memory, bay laurel oil at 100 mg per kg improved maze performance and lowered signs of oxidative damage in the brain. This is mouse work with a dose given to the animals (the abstract does not say how), not a smell. It does not show a memory benefit in people. | 15 | |
| Gut Health | Not enough evidence | Stomach bacteria in a dish (Pimenta racemosa stem and leaf oil, lab): In a test tube, West Indian bay stem oil stopped Helicobacter pylori growth at 3.9 microgram per mL. The antibiotic clarithromycin did it at 1.95 in the same test. This is bacteria in a dish and says nothing about people. | 1 | |
| Digestive Support | Not enough evidence | Stomach bacteria in a dish (Pimenta racemosa stem and leaf oil, lab): In a test tube, West Indian bay stem oil stopped Helicobacter pylori growth at 3.9 microgram per mL. The antibiotic clarithromycin did it at 1.95 in the same test. This is bacteria in a dish and says nothing about people. | 1 | |
| Cellular Protection | Not enough evidence | Antioxidant and enzyme-blocking tests (Pimenta racemosa leaf oil and Laurus nobilis leaf oil, lab): Both oils scored well in chemical antioxidant tests and blocked several enzymes in test tubes. Authors speculate about uses for Alzheimer's, diabetes and skin pigmentation, but they ran no animal or human tests and call for them. | 5 6 | |
| Healthy Aging | Not enough evidence | Antioxidant and enzyme-blocking tests (Pimenta racemosa leaf oil and Laurus nobilis leaf oil, lab): Both oils scored well in chemical antioxidant tests and blocked several enzymes in test tubes. Authors speculate about uses for Alzheimer's, diabetes and skin pigmentation, but they ran no animal or human tests and call for them. | 5 6 | |
| Insect Protection | Not enough evidence | Killing ticks in the lab (Pimenta racemosa oil): West Indian bay oil, mostly eugenol, killed tick larvae, nymphs and adults in a laboratory test. Clove oil and eugenol did too. It was not tested as a repellent on people or pets, and it is not an evidence-based tick protection. | 7 |
B. Body systems
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Cardiovascular System | Biological association | Very low certainty | Studied for: Blood pressure after breathing bay laurel oil vapour (Laurus nobilis, women with hypertension) | 17 |
| Nervous System | Biological association | Not enough evidence | Studied for: Memory in mice (Laurus nobilis oil, mouse study) | 15 |
| Digestive System | Biological association | Not enough evidence | Studied for: Stomach bacteria in a dish (Pimenta racemosa stem and leaf oil, lab) | 1 |
| Cells | Biological association | Not enough evidence | Studied for: Antioxidant and enzyme-blocking tests (Pimenta racemosa leaf oil and Laurus nobilis leaf oil, lab) | 5 6 |
| Whole Body | Biological association | Not enough evidence | Studied for: Killing ticks in the lab (Pimenta racemosa oil) | 7 |
E. Health conditions
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Contact dermatitis | Documented risk (laurel oil); eugenol is a known sensitiser | Review and case reports for laurel; no patch-test data for West Indian bay. Preparation or compound: Laurus nobilis oil; eugenol-rich Pimenta racemosa oil |
18 16 12 | |
| High blood pressure | Very low certainty | One short inhalation study; no numbers in the abstract. Preparation or compound: Bay laurel oil vapour |
17 |
I. Biomarkers
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Blood pressure (systolic and diastolic) | Biological association | Very low certainty | Measured in trials: decrease. A lab change is not the same as a health benefit. | 17 |
| Lowest concentration that stops H. pylori growth | Biological association | Not enough evidence | Measured in trials: decrease. A lab change is not the same as a health benefit. | 1 |
J. Genes, receptors and enzymes
L. Active compounds
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Eugenol | Biological association | Lab and human skin and case data | A known skin sensitiser. High-dose ingestion can injure the liver (LiverTox, clove oil). Antioxidant in lab tests. Preparation or compound: Pimenta racemosa leaf and stem oil; small amounts in Laurus nobilis leaf oil |
25 1 5 7 6 12 10 |
| 1,8-Cineole (eucalyptol) | Biological association | Composition and computer work | The main compound of the laurel oils analysed. Docked to acetylcholinesterase in computer work (mouse paper). Preparation or compound: Laurus nobilis leaf oil |
26 6 15 |
| Methyleugenol | Biological association | Laboratory and animal | Described as genotoxic and carcinogenic in rodents (2025 paper and 2023 review). No human risk figure for laurel oil was found. Preparation or compound: Laurus nobilis leaf oil |
27 6 8 4 |
| Other main compounds | Biological association | Composition only | Composition only; no separate activity read. Preparation or compound: Both oils |
5 6 |
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 Bay 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 19 PubMed records (three had no abstract and were read as titles only) and the Poison Control, Pet Poison Helpline and FDA pages and the US food-additive list, and checked both plant names in GBIF and the compounds in PubChem. We could not read the full text of the blood-pressure study.
Study library: every study we checked 28
| Study | Design | People | Product, dose, length | Result |
|---|---|---|---|---|
| Ayoub 2022 Valorization of Pimenta racemosa Essential Oils and Extracts: GC-MS and LC-MS Phytochemical Profiling and Evaluation of Helicobacter pylori Inhibitory Activity Molecules · PMID 36432065 · DOI |
Laboratory and computer study bacteria / in silico |
Bacteria in a dish; oil and extracts from leaves and stems | Essential oils of Pimenta racemosa leaves and stems (and methanol extracts) essential oil (leaves and stems) Test-tube concentrations n/a · vs Clarithromycin (antibiotic) |
Eugenol made up 57.84% of leaf oil and 59.76% of stem oil (21 compounds). Stem oil stopped H. pylori growth at 3.9 microgram per mL against 1.95 for clarithromycin. MIC 3.9 vs 1.95 microgram per mL Methods, limits and fundingOutcomes: Oil composition (GC-MS); Helicobacter pylori growth inhibition (MIC); computer binding to urease Limitations: Test-tube and computer work only. Says nothing about swallowing the oil or treating infection in people. Funding and conflicts: Authors declare no conflict of interest. Read: abstract |
| Brás 2015 Allergic contact dermatitis caused by laurel leaf oil Contact Dermatitis · PMID 25753052 · DOI |
Case report |
Not stated (no abstract on PubMed) | Laurel leaf oil essential oil (leaves) Not stated Not stated · vs n/a |
No abstract is available. The title says laurel leaf oil caused allergic contact dermatitis. Case report (title only) Methods, limits and fundingOutcomes: Skin allergy Limitations: Only the title and journal record were read. Details unknown. Funding and conflicts: Not stated. Read: title only |
| Casamassima 2017 Dietary effect of dried bay leaves (Laurus nobilis) meal on some biochemical parameters and on plasma oxidative status in New Zealand white growing rabbit J Anim Physiol Anim Nutr (Berl) · PMID 27553760 · DOI |
Controlled animal feeding trial rabbit |
120 120 growing rabbits |
Dried bay leaf meal in feed dried leaf (not oil) 1 g per kg feed (rabbit feed) Growing period · vs Control feeds with and without added fat |
Rabbits fed dried bay leaf meal had lower cholesterol, glucose and liver enzymes and better oxidative markers. This is dried leaf in animal feed, not essential oil. Reported significant decreases in the abstract (no numbers extracted) Methods, limits and fundingOutcomes: Blood fats, liver enzymes, oxidative markers Limitations: Animal feed trial with dried leaf. Not evidence for the oil or for people. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Eisenreich 2025 Comparative Analysis of Estragole, Methyleugenol, Myristicin, and Elemicin Regarding Micronucleus Formation in V79 Cells Molecules · PMID 40005118 · DOI |
Laboratory cell study hamster cells |
n/a Hamster cells in a dish |
Methyleugenol and related compounds compounds Lab n/a · vs n/a |
Opens by saying estragole and methyleugenol are known to be genotoxic and carcinogenic in rodents. In this cell test the methyleugenol result was equivocal (a small change without a dose trend), and the authors say standard cell tests have limited power to judge these compounds. Equivocal for methyleugenol Methods, limits and fundingOutcomes: Micronucleus formation (a marker of DNA damage) Limitations: Cell test; rodent findings are not proof of the same harm in people at skin or scent exposure. Funding and conflicts: No conflicts declared. Read: abstract |
| Eldahshan 2025 Chemical profile of essential oil from Pimenta racemosa leaves, antioxidant potential, and its enzyme inhibitory properties Sci Rep · PMID 40841731 · DOI |
Laboratory chemical study none (chemical assays) |
Leaf oil from plants grown in Egypt (Pimenta racemosa var. racemosa) | Essential oil of Pimenta racemosa leaves essential oil (leaves) Test-tube n/a · vs None stated |
Fourteen compounds (99.76%): eugenol 70.87%, beta-myrcene 12.88%, D-limonene 8.35%. The oil scored high in several chemical antioxidant tests and blocked several enzymes in the test tube. The authors say further toxicology, animal and clinical studies are needed. Not applicable (chemical assays) Methods, limits and fundingOutcomes: Oil composition (GC-MS); antioxidant tests; enzyme-blocking tests (acetylcholinesterase, butyrylcholinesterase, tyrosinase, alpha-glucosidase, alpha-amylase) Limitations: Chemical tests only. Antioxidant scores in a test tube do not show benefit in people. Funding and conflicts: Authors declare no competing interests. Read: abstract |
| Fantasma 2024 Essential Oils of Laurus nobilis L.: From Chemical Analysis to In Silico Investigation of Anti-Inflammatory Activity by Soluble Epoxide Hydrolase (sEH) Inhibition Foods · PMID 39063366 · DOI |
Laboratory and computer study none (chemical assays) |
Wild laurel leaves from seven places at different heights in central Italy | Essential oils of Laurus nobilis leaves (hydrodistillation) essential oil (leaves) Test-tube n/a · vs None stated |
78 compounds were identified. Main ones across the seven oils: 1,8-cineole 43.52 to 31.31%, methyl-eugenol 14.96 to 4.07%, alpha-terpinyl acetate 13.00 to 8.51%, linalool 11.72 to 1.08%, sabinene, alpha-pinene, eugenol 4.12 to 1.97%. The oils showed antioxidant and enzyme-blocking activity in the lab. Not applicable Methods, limits and fundingOutcomes: Oil composition (GC-FID, GC/MS); antioxidant tests; enzyme (sEH) blocking; computer docking Limitations: Lab and computer work only. The abstract says folk medicine uses laurel infusion or decoction for gut complaints and gas, but this paper tested none of that in people. Funding and conflicts: Authors declare no conflicts of interest. Read: abstract |
| Gao 2024 The contact toxicity and toxic mechanism of essential oils from Pimenta racemosa and Eugenia caryophyllata against Haemaphysalis longicornis (Acari: Ixodidae) Pestic Biochem Physiol · PMID 39084793 · DOI |
Laboratory tick study tick |
Unfed larvae, nymphs and adults of the Asian longhorned tick in a lab | Essential oils of Pimenta racemosa (eugenol 64.07%) and clove (Eugenia caryophyllata) essential oil Lab concentrations on ticks n/a · vs Clove oil and eugenol |
Pimenta racemosa oil killed ticks in the lab: LC50 1.20 mg per mL for larvae and 0.51 mg per mL for adults. Clove oil and eugenol also killed ticks. LC50 1.20 (larvae), 1.65 (nymphs), 0.51 (adults) mg per mL Methods, limits and fundingOutcomes: Tick death (LC50) Limitations: Ticks in a lab test. It is not a test of a repellent on people or pets. Funding and conflicts: Authors declare no competing interests. Read: abstract |
| Götz 2023 Occurrence of Alkenylbenzenes in Plants: Flavours and Possibly Toxic Plant Metabolites Plants (Basel) · PMID 37299054 · DOI |
Review by the German Federal Institute for Risk Assessment review |
n/a Review of essential oils and extracts used for flavouring |
Alkenylbenzenes (safrole, methyleugenol, estragole) in plant oils essential oils and extracts n/a n/a · vs n/a |
Says some alkenylbenzenes are proven genotoxic carcinogens (it names safrole, methyleugenol and estragole as widely known genotoxic examples) and that data on how much is in plant foods and supplements are limited. Qualitative Methods, limits and fundingOutcomes: Occurrence of possibly toxic alkenylbenzenes Limitations: It does not say how much methyleugenol is in laurel or West Indian bay oil, and does not assess skin or air exposure. Funding and conflicts: No competing interests declared. 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 plus database analysis (UK) |
1 A 15-month-old boy |
Clove oil swallowed (10 ml) clove oil 10 ml (accidental) Single ingestion · vs n/a |
The boy developed fulminant hepatic failure after swallowing 10 ml of clove oil; ALT was above 13,000 U/l after 24 hours. His liver recovered after intravenous N-acetylcysteine in hospital. A national database showed a 14-fold rise in home accidents related to aromatherapy from 1994 to 1999. ALT above 13,000 U/l at 24 h; recovered Methods, limits and fundingOutcomes: Liver function after swallowing Limitations: One child. Clove oil, not bay oil. Bay oil is also eugenol-rich but no bay oil case was found. Funding and conflicts: Not stated in the abstract. Read: abstract |
| LiverTox 2019 Eugenol (Clove Oil). LiverTox: Clinical and Research Information on Drug-Induced Liver Injury (updated 2019-10-28) LiverTox (NIH Bookshelf) · PMID 31869191 |
US government drug liver injury database entry |
n/a n/a |
Eugenol / clove oil clove oil (eugenol) Not covered here n/a · vs n/a |
Says eugenol is used as a food flavouring and sometimes on skin for toothache, or rarely taken by mouth. Eugenol in therapeutic doses has not been implicated in raised liver enzymes or clinically apparent liver injury, but ingestion of high doses, as in an overdose, can cause severe liver injury. Qualitative statement Methods, limits and fundingOutcomes: Liver injury Limitations: The entry is about clove oil and eugenol. Bay oil is not named. Funding and conflicts: Public database. Read: abstract (PubMed record of the entry) |
| Navarro Triviño 2019 Eugenol allergy mimicking recurrent aphthous stomatitis and burning mouth syndrome Contact Dermatitis · PMID 31373017 · DOI |
Case report |
Not stated (no abstract on PubMed) | Eugenol eugenol Not stated Not stated · vs n/a |
No abstract is available. The title says eugenol allergy mimicked recurrent mouth ulcers and burning mouth. Case report (title only) Methods, limits and fundingOutcomes: Mouth complaints Limitations: Only the title was read. Not a bay oil report. Funding and conflicts: Not stated. Read: title only |
| Ofenloch 2023 Allergic reactivity for different dilutions of eugenol in repeated open application test and patch testing Contact Dermatitis · PMID 37218587 · DOI |
Patch test and repeated open application test |
67 67 people from 6 European skin clinics; 34 had contact allergy to eugenol |
Eugenol (single compound) on skin eugenol Test dilutions 2.7% to 0.5% (open test); 2.0% to 0.00006% (patch) 21 days twice daily (open test) · vs Control solution |
Eugenol is a known contact sensitiser and part of fragrance mix I. Of 34 allergic subjects, 21 (61.8%) had a positive patch test before the open test; the lowest positive concentration was 0.031%. The open test was positive in 19 (55.9%). In 13 (38.2%) the patch test result was not reproducible, yet 4 of those 13 had a positive open test. Lowest positive patch concentration 0.031% Methods, limits and fundingOutcomes: Positive patch and open-application reactions Limitations: Tested pure eugenol, not bay oil. People were selected because they were already allergic. It cannot give a rate of allergy for bay oil in the public. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Parlow 2022 Persistent contact dermatitis following use of laurel oil J Dtsch Dermatol Ges · PMID 35060293 · DOI |
Letter / case report |
Not stated (no abstract on PubMed) | Laurel oil essential oil Not stated Not stated · vs n/a |
No abstract is available. The title says contact dermatitis that persisted followed use of laurel oil. Case report (title only) Methods, limits and fundingOutcomes: Skin allergy Limitations: Only the title and journal record were read. Details unknown, including which laurel oil. Funding and conflicts: Not stated. Read: title only |
| Port-Lougarre 2023 Antioxidant Activity and Skin Sensitization of Eugenol and Isoeugenol: Two Sides of the Same Coin? Chem Res Toxicol · PMID 37922503 · DOI |
Laboratory study on reconstructed human skin lab skin model |
Reconstructed human epidermis (lab) | Eugenol and isoeugenol compounds Lab n/a · vs n/a |
States that eugenol and isoeugenol are important skin sensitisers and that the cosmetics and fragrance industries must notify their presence in products. The study explored how radicals formed in lab skin may lead to sensitisation. Not applicable Methods, limits and fundingOutcomes: How eugenol may cause skin sensitisation Limitations: Lab study on lab skin. The mechanism is a proposal. Funding and conflicts: Not stated in the abstract. Read: abstract |
| Smach 2024 Neuroprotective and anti-amnesic effects of Laurus Nobilis essential oil against scopolamine-induced memory deficits in mice brain J Ethnopharmacol · PMID 37689325 · DOI |
Mouse study with docking mouse |
Not stated in the abstract Mice given scopolamine to impair memory |
Essential oil of Laurus nobilis leaves from Tunisia (main compounds 1,8-cineole and alpha-terpinyl acetate) essential oil (leaves) 100 mg per kg body weight (mouse dose, not a human dose) Chronic · vs Mice given scopolamine without oil |
Oil treatment improved test performance and reduced oxidative damage compared with scopolamine alone (p < 0.05). Computer docking suggested 1,8-cineole and alpha-terpinyl acetate bind acetylcholinesterase. p < 0.05 versus scopolamine group Methods, limits and fundingOutcomes: Memory tests (Morris water maze, Y maze); brain markers of oxidative damage and cholinergic enzyme activity Limitations: Mouse study. The dose was given by dosing, not by smelling the oil. Not shown in people. Funding and conflicts: Authors declare no competing interests. Read: abstract |
| Uzuncakmak 2015 Erythema multiforme like allergic contact dermatitis associated with laurel oil: a rare presentation Dermatol Online J · PMID 25933076 |
Case report |
1 A patient with an allergic skin reaction linked to laurel oil (details not in the abstract) |
Laurus nobilis essential oil essential oil Not stated Not stated · vs n/a |
The abstract says Laurus nobilis essential oil is widely used in massage therapy, that laurel-induced contact dermatitis has been reported before, and that an erythema-multiforme-like pattern is rare. Case report Methods, limits and fundingOutcomes: Type of skin reaction Limitations: The PubMed abstract is short and gives no patient details. Funding and conflicts: Not stated. Read: abstract |
| Yarosh 2023 Impact of essential oil vapors inhalation on blood pressure in patients with hypertension (Russian journal; English abstract) Vopr Kurortol Fizioter Lech Fiz Kult · PMID 37141519 · DOI |
Controlled inhalation study of 23 oils, women with hypertension, Crimea (Russia) |
849 849 women aged 55 to 89 with high blood pressure, divided into a control group and groups for each oil |
Essential oil vapour of about 23 plants, including bay laurel (named in the Russian text as 'lavr blagorodnyi', the usual Russian name of Laurus nobilis) and clove tree; 1 mg per cubic metre of air essential oil (plant part not stated) Not covered here One procedure; two series of 10 and 20 minutes · vs Control group had the psychorelaxation procedure without oil |
The abstract says bay laurel oil showed antihypertensive action at both 10-minute and 20-minute exposure. It gives no blood-pressure numbers, no group sizes per oil and no p-values. Clove tree oil worked after 10 minutes only. Several oils (for example lavender, peppermint, fennel) showed no effect. Not given in the abstract. Methods, limits and fundingOutcomes: Systolic and diastolic blood pressure and heart rate before and after one session Limitations: The abstract gives no numbers, so size and certainty of the drop cannot be judged. One short session, so nothing is known about lasting effect. Only the abstract (English and Russian) was read. Whether the control group could tell it was not receiving a scent is not stated. Funding and conflicts: Not stated in the abstract. Authors are at a botanical garden. Read: abstract |
| de Groot 2016 Essential Oils, Part IV: Contact Allergy Dermatitis · PMID 27427818 · DOI |
Review |
n/a People patch-tested for suspected contact dermatitis (review) |
Essential oils on skin (review); laurel among them essential oils Not covered here n/a · vs n/a |
Nearly 80 essential oils have caused contact allergy. Fifty-five were tested in consecutive patients suspected of contact dermatitis. Nine, including laurel and clove, gave more than 2% positive patch tests. Relevance data are generally missing or inadequate. Most reactions come from pure oils or high-concentration products. Massage professionals may get occupational dermatitis. More than 2% positive for laurel (and eight other oils) Methods, limits and fundingOutcomes: Which oils cause contact allergy Limitations: The abstract does not say which laurel oil or how many people were tested. Patients were already suspected of allergy, so the rate in the general public is lower. West Indian bay is not named in the abstract. Funding and conflicts: Not stated in the abstract. Read: abstract |
| n/a 2024 Poison Control (US): Essential oils, poisonous when misused (page read 2026-10-25) n/a · Source |
Poison centre public page n/a |
n/a | n/a n/a n/a n/a · vs n/a |
Says many essential oils can cause rashes and some are poisonous if absorbed through skin or swallowed. Aspirating an oil (choking so some enters the lungs) can cause pneumonia. Children have thin skin and immature livers and may be more susceptible. Essential oils may interact with medicines. Pure oils are potent and are diluted in a carrier oil for skin; do not use on damaged skin; stop and wash off if a rash appears. It can be hard to know the species, concentration or contaminants in a bottle. If someone swallows an essential oil call 1-800-222-1222 (US). Bay and eugenol are not named on the page. Methods, limits and fundingOutcomes: General essential-oil safety Limitations: General guidance for essential oils; it names no bay case. Read: full-text |
| n/a 2025 US Code of Federal Regulations, 21 CFR 182.20: Essential oils, oleoresins and natural extractives (eCFR version dated 2025-01-01, read 2026-10-25) n/a · Source |
US food regulation n/a |
n/a | n/a n/a n/a n/a · vs n/a |
The list of essential oils generally recognised as safe (GRAS) for their intended use as food additives includes 'Bay leaves, Laurus nobilis L.' and 'Bay (myrcia oil), Pimenta racemosa (Mill.) J. W. Moore'. Methods, limits and fundingOutcomes: Food-additive status of bay oils Limitations: This is about use as a food flavouring. It is not a finding about aromatherapy, skin use, swallowing bottled oil, children or pets. Read: full-text |
| n/a 2026 GBIF species match API: Pimenta racemosa (Mill.) J.W.Moore (checked 2026-10-25) n/a · Source |
Taxonomy database n/a |
n/a | n/a n/a n/a n/a · vs n/a |
Pimenta racemosa (Mill.) J.W.Moore, key 3186096, status ACCEPTED, family Myrtaceae, exact match. Methods, limits and fundingOutcomes: Accepted name Limitations: Name checking only. Read: full-text |
| n/a 2026 GBIF species match API: Laurus nobilis L. (checked 2026-10-25) n/a · Source |
Taxonomy database n/a |
n/a | n/a n/a n/a n/a · vs n/a |
Laurus nobilis L., key 3034015, status ACCEPTED, family Lauraceae, exact match. Methods, limits and fundingOutcomes: Accepted name Limitations: Name checking only. Read: full-text |
| n/a 2026 Pet Poison Helpline: Essential oils (page read 2026-10-25) n/a · Source |
Veterinary poison centre public page n/a |
n/a | n/a n/a n/a n/a · vs n/a |
Says essential oil toxicosis can affect all species but cats and birds are at greatest risk; signs usually develop within 6 to 8 hours with most essential oils. Its list of oils of concern includes clove. Bay is not named. US line 800-213-6680. Methods, limits and fundingOutcomes: Essential oil poisoning in pets Limitations: General page. Bay oil is not named. Read: full-text |
| n/a 2026 FDA: Aromatherapy (page read 2026-10-25) n/a · Source |
US regulator public page n/a |
n/a | n/a n/a n/a n/a · vs n/a |
Says how an aromatherapy product is regulated depends on its intended use: meant to smell good = cosmetic (no FDA approval before sale); claims to treat disease or ease pain make it a drug. Methods, limits and fundingOutcomes: How aromatherapy products are regulated Limitations: General rules; not about bay oil. Read: full-text |
| n/a 2026 PubChem: Eugenol, CID 3314 (checked 2026-10-25) n/a · Source |
Chemistry database n/a |
n/a | n/a n/a n/a n/a · vs n/a |
Eugenol, CID 3314, C10H12O2, 2-methoxy-4-prop-2-enylphenol. Methods, limits and fundingOutcomes: Compound identity Limitations: Identity only. Read: full-text |
| n/a 2026 PubChem: 1,8-Cineole, CID 2758 (checked 2026-10-25) n/a · Source |
Chemistry database n/a |
n/a | n/a n/a n/a n/a · vs n/a |
1,8-Cineole (eucalyptol), CID 2758, C10H18O. Methods, limits and fundingOutcomes: Compound identity Limitations: Identity only. Read: full-text |
| n/a 2026 PubChem: Methyleugenol, CID 7127 (checked 2026-10-25) n/a · Source |
Chemistry database n/a |
n/a | n/a n/a n/a n/a · vs n/a |
Methyleugenol, CID 7127, C11H14O2, 1,2-dimethoxy-4-prop-2-enylbenzene. Methods, limits and fundingOutcomes: Compound identity Limitations: Identity only. Read: full-text |
| Çabuk 2014 Effects of herbal essential oil mixture as a dietary supplement on egg production in quail ScientificWorldJournal · PMID 24587729 · DOI |
Controlled animal feeding trial quail |
180 180 laying quail |
A mixture of six essential oils including laurel leaf oil, in feed essential oil mixture 24 mg per kg feed (quail feed) 12 weeks · vs Control diet and an antibiotic diet |
The mixture raised egg production versus the control, similar to the antibiotic. It cannot show what laurel oil does alone. P < 0.001 for egg production versus control Methods, limits and fundingOutcomes: Egg production, feed use Limitations: Mixture of six oils in poultry feed. Not evidence for people. Funding and conflicts: Not stated in the abstract. Read: abstract |
What we do not know yet
- What the evidence supports: one very-low-certainty scent study for blood pressure; everything else is insufficient.
- No human trial of West Indian bay oil was found.
- No patch-test study of West Indian bay oil, and no bay oil poisoning report, was found; the liver warning is read across from clove oil and eugenol.
- No source on pregnancy, breastfeeding, children, pets, asthma, seizures or sun sensitivity for bay oils.
- The blood-pressure abstract gives no numbers, and the full paper was not read.
- No EMA, EFSA, SCCS, IFRA, Tisserand or LactMed statement on bay 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 2
Blood pressure (systolic and diastolic)
Decrease in trials
The pressure of blood in the arteries, measured with a cuff.
Very low certaintyResults and what it means
Why it was measured
Main outcome of the inhalation study.
Statistical vs. clinical meaning
One short study with no numbers in its abstract.
Safety implication
Not a replacement for blood-pressure medicine.
| Study | Result | People | Product |
|---|---|---|---|
| 17 | Bay laurel oil vapour was reported to have antihypertensive action at 10 and 20 minutes. No values given in the abstract. |
Lowest concentration that stops H. pylori growth
Decrease in trials
The lowest amount of a substance that stops bacteria growing in a dish.
Not enough evidenceResults and what it means
Why it was measured
Main outcome of the Pimenta racemosa lab study.
Statistical vs. clinical meaning
A test-tube number; it does not predict an effect in the stomach.
Safety implication
Do not use oil for stomach infection.
| Study | Result | People | Product |
|---|---|---|---|
| 1 | Stem oil 3.9 microgram per mL against 1.95 for clarithromycin. |
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 5
- 'Bay oil' can mean two different oils. Check the Latin name.. West Indian bay is Pimenta racemosa (myrtle family) and its oil is mostly eugenol: 57.84% to 70.87% in the lab analyses we read. Bay laurel is Laurus nobilis (laurel family) and its oil is led by 1,8-cineole with some methyl-eugenol (4.07 to 14.96%) and eugenol (1.97 to 4.12%). Their risks are not the same, and most of what is known is about one or the other, not both. Lab analysis 5 1 6 21 22
- Laurel oil is a documented skin allergen.. A review of essential-oil contact allergy lists laurel among nine oils that gave more than 2% positive patch tests in people suspected of contact dermatitis. Case reports link laurel oil to allergic rashes, including one persistent rash and one that looked like erythema multiforme. The review says most reactions follow pure oils or high-concentration products. Stop and wash off if a rash appears, and see a doctor. Review and case reports 18 16 2 13 19
- Eugenol, the main compound of West Indian bay oil, is a known skin sensitiser.. Eugenol is part of fragrance mix I. In 34 people with eugenol allergy, patch tests were positive at concentrations as low as 0.031%, and the allergy could persist even when a patch test could not be repeated. No patch-test study of West Indian bay oil itself was found, so we cannot say how often it reacts. Clinical study (eugenol alone) 12 14
- Do not swallow bay oil. Eugenol overdose can injure the liver.. LiverTox says eugenol at therapeutic doses has not been linked to liver injury, but a high-dose ingestion can cause severe liver injury. A 15-month-old boy developed liver failure after swallowing 10 ml of clove oil, which is also eugenol-rich, and recovered with hospital treatment. No poisoning case with bay oil itself was found, so eugenol content is the reason for caution, not proof of the same outcome. Poison Control also warns that choking oil into the lungs can cause pneumonia. If anyone, child or pet, may have swallowed an essential oil, call poison control (US 1-800-222-1222) or your emergency number. Regulatory and case report 10 9 19
- Laurel oil contains methyl-eugenol, which is a rodent carcinogen.. Italian laurel leaf oils held 4.07 to 14.96% methyl-eugenol. A German federal risk-assessment review names methyleugenol among widely known genotoxic alkenylbenzenes, and a 2025 paper says it is genotoxic and carcinogenic in rodents. We found no study that measures the risk from laurel oil used on skin or in the air, so no risk figure can be given. How much methyl-eugenol West Indian bay oil holds was not in the sources we read. Lab and animal 6 8 4
Side effects 4
| Effect | How often | Severity and recovery | Evidence |
|---|---|---|---|
| Allergic contact dermatitis (itchy, red rash where the oil touched the skin) The case reports about laurel oil were read as titles or short abstracts only. | Laurel gave more than 2% positive patch tests in consecutive patients suspected of contact dermatitis (review). Not the rate in the general public. No rate for West Indian bay. | mild to moderate; one case was persistent Usually settles when contact stops; allergy tends to persist. | Review and case reports 18 16 2 13 |
| Eugenol allergy, including mouth complaints A case report title says eugenol allergy mimicked recurrent mouth ulcers and burning mouth. Details were not read. | Among 34 eugenol-allergic people, 21 (61.8%) had a positive patch test; the lowest positive concentration was 0.031%. | mild to moderate Not stated. | Clinical study and case report (title only) 12 11 |
| Severe liver injury after swallowing a large amount of an eugenol-rich oil (clove oil) Clove oil, not bay oil. See the liver section. | One reported toddler (10 ml). Frequency unknown. | severe, life-threatening The boy recovered after intravenous N-acetylcysteine in hospital. | Case report 9 10 |
| Pneumonia if oil is breathed into the lungs while swallowing General essential-oil warning. | Not stated. | serious Not stated. | Regulatory 19 |
Liver
West Indian bay oil is mostly eugenol (57.84% to 70.87% in the analyses read). LiverTox says eugenol in therapeutic doses has not been linked to liver injury but that high-dose ingestion can cause severe injury. The one case we found was a toddler who swallowed clove oil. We found no liver case with bay oil. Do not swallow any essential oil. 10 9 5
How often. No bay oil cases found.
Monitoring. Yellow skin or eyes, dark urine, severe tiredness or pain in the upper right belly after any oil needs a doctor straight away.
- . A 15-month-old boy swallowed 10 ml of clove oil and developed fulminant liver failure (ALT above 13,000 U/l after 24 hours). He recovered after intravenous N-acetylcysteine. 9
This is a safety connection. It is not evidence that Bay Oil supports liver health.
Medicines and supplements 1
| With | Why it matters | Importance | Evidence | What to do |
|---|---|---|---|---|
| Prescription and other medicines general medicine interactions | Poison Control says essential oils may interact with medicines. No interaction with bay oil is named in any source we read. | Not established. | Regulatory Not enough evidence 19 | Ask a pharmacist, especially if you take liver-affecting medicines or any medicine regularly. |
Who should check first 5
| Situation | Advice | Evidence |
|---|---|---|
| Known allergy to laurel, eugenol, clove, or fragrance mix I (a common patch-test allergy marker) | Avoid bay oils and products that contain them. Ask a doctor about patch testing. | Clinical study and review 18 12 |
| Broken or inflamed skin | Poison Control says not to use essential oils on damaged skin. | Regulatory 19 |
| Babies and young children | Keep bottles out of reach and away from their faces. Poison Control says children have thin skin and immature livers and may be more susceptible. Eugenol-rich clove oil caused liver failure in a toddler. No bay oil source for children was found. | Regulatory and case report 19 9 |
| Cats, dogs and birds | Keep oils and diffusers away. Pet Poison Helpline says cats and birds are at greatest risk of essential-oil poisoning and lists clove among oils of concern. Bay is not named, and we found no source on bay oil in pets. | Veterinary poison centre 23 |
| Pregnancy and breastfeeding | No bay oil source was found. Ask a doctor or midwife before using any essential oil. | Gap 19 |
Overdose, product quality and regulators
Summary. Bay-oil-specific poisoning data were not found. Eugenol-rich oils can injure the liver in overdose, laurel oil is a documented skin allergen, and general essential-oil sources warn of lung damage if aspirated and pet risk.
Amounts. No safe amount is established, and this page gives none.
Onset and course. For pets, Pet Poison Helpline says signs usually develop within 6 to 8 hours with most essential oils (general page). For people, no bay-specific course was found.
Repeated use. Eugenol allergy can persist; one study found hypersensitivity even when a former positive patch test was not reproducible.
Animal data. Methyleugenol is genotoxic and carcinogenic in rodents (as stated by a 2025 paper and a 2023 review). Laurel oil contained 4.07 to 14.96% methyl-eugenol in Italian samples. Cats and birds are at greatest risk of essential-oil poisoning (Pet Poison Helpline, general).
Toxic parts. The essential oil is the concentrated form. Oil makeup varies by species, place and batch.
Not read. No EMA, EFSA, SCCS or IFRA statement on bay oil, no LactMed entry, no Tisserand bay maximum, and no ASPCA entry for bay were read.
Essential oil products are not tightly regulated, so what is in the bottle can differ from the label.
Unknown species, strength and contaminants. Poison Control says it can be hard to know the species, concentration or contaminants in an essential oil bottle. 19
Two plants, different chemistry. Oil from Pimenta racemosa was 57.84% to 70.87% eugenol. Oil from Laurus nobilis was led by 1,8-cineole (31.31% to 43.52%) with 4.07% to 14.96% methyl-eugenol. The place, plant part and batch change these numbers. 5 1 6
Cosmetic or drug. The FDA says a product with claims to treat disease or ease pain is a drug, while a product meant only to make someone smell good is a cosmetic, which needs no FDA approval before sale. 24
| Body | Action | Date |
|---|---|---|
| US FDA, 21 CFR 182.20 (GRAS essential oils) (United States) | Lists 'Bay leaves' (Laurus nobilis L.) and 'Bay (myrcia oil)' (Pimenta racemosa (Mill.) J. W. Moore) among essential oils generally recognised as safe for their intended use as food additives. This is a food-flavouring rule, not a finding about aromatherapy, skin use or swallowing bottled oil. source | 2025-01-01 |
| US FDA, Aromatherapy page (United States) | Says an aromatherapy product's regulatory status depends on its intended use; claims to treat disease or ease pain make it a drug, and cosmetics need no pre-market approval. source | |
| NIH LiverTox, Eugenol (Clove Oil) (United States) | Says high-dose eugenol ingestion (as in overdose) can cause severe liver injury; therapeutic doses have not been implicated. source | 2019-10-28 |
| Poison Control (National Capital Poison Center) (United States) | General essential-oil warnings: poisonous if swallowed or absorbed, aspiration pneumonia, children more susceptible, dilute and avoid damaged skin. source |
When to get medical help
- If a child or pet may have swallowed any essential oil, call poison control (US: 1-800-222-1222; Pet Poison Helpline 800-213-6680) or your emergency number.
- Trouble breathing, coughing or choking after oil was swallowed or breathed in needs urgent care (risk of pneumonia).
- Swelling of the lips, tongue or face, or a spreading rash after contact is an emergency.
- Yellow skin or eyes, dark urine, or severe tiredness or belly pain after swallowing an oil needs a doctor straight away.
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 bay oil the same as bay laurel oil?
Not always. West Indian bay (Pimenta racemosa) and bay laurel (Laurus nobilis) are different plants in different families. West Indian bay oil is mostly eugenol (57.84% to 70.87% in lab analyses). Laurel oil is led by 1,8-cineole with some methyl-eugenol. Check the Latin name on the label.
Can bay oil cause a skin reaction?
Yes. Laurel oil gave more than 2% positive patch tests in a review of people suspected of contact dermatitis, and case reports link it to allergic rashes. Eugenol, the main compound in West Indian bay oil, is a known skin sensitiser. We found no patch-test study of West Indian bay oil. Stop and wash off if a rash appears, and see a doctor.
Can I swallow bay oil?
We do not advise swallowing any essential oil. LiverTox says high-dose eugenol can cause severe liver injury, and a toddler developed liver failure after swallowing clove oil, which is also eugenol-rich. No bay oil case was found. If anyone may have swallowed an essential oil, call poison control (US 1-800-222-1222) or your emergency number.
Is bay oil safe for babies and children?
Is bay oil safe around cats, dogs and birds?
Keep it away. Pet Poison Helpline says cats and birds are at greatest risk of essential-oil poisoning and lists clove among oils of concern. It does not name bay, and we found no source on bay oil in pets. Call your vet or a pet poison line if a pet may have been exposed.
Is bay oil safe in pregnancy or while breastfeeding?
We found no source on either bay oil in pregnancy or breastfeeding, so we cannot say. Ask a doctor or midwife before using any essential oil.
Does bay oil lower blood pressure?
Maybe, but the evidence is very low. One short study reported lower blood pressure in women with hypertension after breathing bay laurel vapour for 10 or 20 minutes, against a relaxation-only control. The abstract gives no numbers. Do not use it in place of blood-pressure medicine.
Does bay oil help memory?
Not shown in people. In mice given a memory-impairing drug, laurel oil improved maze tests. That is animal work with a dose given to the mice, not a smell.
Does bay oil kill stomach bacteria or ticks?
What is methyl-eugenol and should I worry?
It is a compound found in bay laurel oil (4.07% to 14.96% in Italian leaf oils). A 2025 paper says it is genotoxic and carcinogenic in rodents. We found no study of the risk from laurel oil used on skin or in the air, so we cannot give a risk figure. We did not find the amount in West Indian bay oil.
Can bay oil interact with medicines?
Poison Control says essential oils may interact with medicines. No bay oil interaction is named in any source we read. Tell your pharmacist about any essential oil you use.
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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 19 PubMed records (three had no abstract and were read as titles only) and the Poison Control, Pet Poison Helpline and FDA pages and the US food-additive list, and checked both plant names in GBIF and the compounds in PubChem. We could not read the full text of the blood-pressure study.
- 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. Trials or assessments linked to industry are labelled.
Sources 28
Each source was opened and checked. Where we read only the abstract, it says so. The small numbers in the text point here.
- Ayoub IM, Abdel-Aziz MM, Elhady SS, et al. Valorization of Pimenta racemosa Essential Oils and Extracts: GC-MS and LC-MS Phytochemical Profiling and Evaluation of Helicobacter pylori Inhibitory Activity. Molecules. 2022. PMID 36432065. DOI 10.3390/molecules27227965. (abstract)
- Brás S, Mendes-Bastos P, Amaro C, Cardoso J. Allergic contact dermatitis caused by laurel leaf oil. Contact Dermatitis. 2015. PMID 25753052. DOI 10.1111/cod.12377. (title only)
- Casamassima D, Palazzo M, Vizzarri F, et al. Dietary effect of dried bay leaves (Laurus nobilis) meal on some biochemical parameters and on plasma oxidative status in New Zealand white growing rabbit. J Anim Physiol Anim Nutr (Berl). 2017. PMID 27553760. DOI 10.1111/jpn.12584. (abstract)
- Eisenreich A, Wittek L, Sagmeister M, et al. Comparative Analysis of Estragole, Methyleugenol, Myristicin, and Elemicin Regarding Micronucleus Formation in V79 Cells. Molecules. 2025. PMID 40005118. DOI 10.3390/molecules30040806. (abstract)
- Eldahshan OA, Nilofar N, Zengin G, El-Nashar HAS. Chemical profile of essential oil from Pimenta racemosa leaves, antioxidant potential, and its enzyme inhibitory properties. Sci Rep. 2025. PMID 40841731. DOI 10.1038/s41598-025-15542-3. (abstract)
- Fantasma F, Samukha V, Aliberti M, et al. Essential Oils of Laurus nobilis L.: From Chemical Analysis to In Silico Investigation of Anti-Inflammatory Activity by Soluble Epoxide Hydrolase (sEH) Inhibition. Foods. 2024. PMID 39063366. DOI 10.3390/foods13142282. (abstract)
- Gao Z, Bai L, Xu X, et al. The contact toxicity and toxic mechanism of essential oils from Pimenta racemosa and Eugenia caryophyllata against Haemaphysalis longicornis (Acari: Ixodidae). Pestic Biochem Physiol. 2024. PMID 39084793. DOI 10.1016/j.pestbp.2024.105992. (abstract)
- Götz ME, Eisenreich A, Frenzel J, et al. Occurrence of Alkenylbenzenes in Plants: Flavours and Possibly Toxic Plant Metabolites. Plants (Basel). 2023. PMID 37299054. DOI 10.3390/plants12112075. (abstract)
- Janes SE, Price CS, Thomas D. Essential oil poisoning: N-acetylcysteine for eugenol-induced hepatic failure and analysis of a national database. Eur J Pediatr. 2005. PMID 15895251. DOI 10.1007/s00431-005-1692-1. (abstract)
- LiverTox, NIDDK. Eugenol (Clove Oil). LiverTox: Clinical and Research Information on Drug-Induced Liver Injury (updated 2019-10-28). LiverTox (NIH Bookshelf). 2019. PMID 31869191. (abstract (PubMed record of the entry))
- Navarro Triviño FJ, Cuenca-Barrales C, Ruiz-Villaverde R. Eugenol allergy mimicking recurrent aphthous stomatitis and burning mouth syndrome. Contact Dermatitis. 2019. PMID 31373017. DOI 10.1111/cod.13365. (title only)
- Ofenloch RF, Andersen KE, Foti C, et al. Allergic reactivity for different dilutions of eugenol in repeated open application test and patch testing. Contact Dermatitis. 2023. PMID 37218587. DOI 10.1111/cod.14333. (abstract)
- Parlow L, Humme D, Ghoreschi FC, et al. Persistent contact dermatitis following use of laurel oil. J Dtsch Dermatol Ges. 2022. PMID 35060293. DOI 10.1111/ddg.14693. (title only)
- Port-Lougarre Y, Gourlaouen C, Vileno B, Giménez-Arnau E. Antioxidant Activity and Skin Sensitization of Eugenol and Isoeugenol: Two Sides of the Same Coin?. Chem Res Toxicol. 2023. PMID 37922503. DOI 10.1021/acs.chemrestox.3c00263. (abstract)
- Smach MA, Hafsa J, Ben Abdallah J, et al. Neuroprotective and anti-amnesic effects of Laurus Nobilis essential oil against scopolamine-induced memory deficits in mice brain. J Ethnopharmacol. 2024. PMID 37689325. DOI 10.1016/j.jep.2023.117151. (abstract)
- Uzuncakmak TK, Karadag AS, Izol B, et al. Erythema multiforme like allergic contact dermatitis associated with laurel oil: a rare presentation. Dermatol Online J. 2015. PMID 25933076. (abstract)
- Yarosh AM, Tonkovtseva VV, Grigoriev PE, et al. Impact of essential oil vapors inhalation on blood pressure in patients with hypertension (Russian journal; English abstract). Vopr Kurortol Fizioter Lech Fiz Kult. 2023. PMID 37141519. DOI 10.17116/kurort202310002122. (abstract)
- de Groot AC, Schmidt E. Essential Oils, Part IV: Contact Allergy. Dermatitis. 2016. PMID 27427818. DOI 10.1097/DER.0000000000000197. (abstract)
- n/a. Poison Control (US): Essential oils, poisonous when misused (page read 2026-10-25). n/a. 2024. (full-text)
- n/a. US Code of Federal Regulations, 21 CFR 182.20: Essential oils, oleoresins and natural extractives (eCFR version dated 2025-01-01, read 2026-10-25). n/a. 2025. (full-text)
- n/a. GBIF species match API: Pimenta racemosa (Mill.) J.W.Moore (checked 2026-10-25). n/a. 2026. (full-text)
- n/a. GBIF species match API: Laurus nobilis L. (checked 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. FDA: Aromatherapy (page read 2026-10-25). n/a. 2026. (full-text)
- n/a. PubChem: Eugenol, CID 3314 (checked 2026-10-25). n/a. 2026. (full-text)
- n/a. PubChem: 1,8-Cineole, CID 2758 (checked 2026-10-25). n/a. 2026. (full-text)
- n/a. PubChem: Methyleugenol, CID 7127 (checked 2026-10-25). n/a. 2026. (full-text)
- Çabuk M, Eratak S, Alçicek A, et al. Effects of herbal essential oil mixture as a dietary supplement on egg production in quail. ScientificWorldJournal. 2014. PMID 24587729. DOI 10.1155/2014/573470. (abstract)