Clove Oil
Clove oil (Syzygium aromaticum) and its main chemical eugenol: toothache claims, documented liver injury in toddlers who swallowed it, skin allergy, and why it is not for swallowing.
Content last updated . This page has not been medically reviewed.
Safety first. Supplements can cause side effects and interact with medicines. Read mushroom safety and interactions before you use any mushroom product.
Urgent first. Clove oil is a poisoning hazard for small children. Case reports describe a 15-month-old boy who developed fulminant (sudden, severe) liver failure after swallowing 10 ml of clove oil, and a 3-month-old girl who developed it after swallowing less than 8 ml. [1][2] Both improved with hospital treatment. [1][2] If a child or pet may have swallowed any essential oil, call Poison Help at 1-800-222-1222 (US); call 911 for collapse, a seizure or trouble breathing. [3] See Poisoning: what to do first. We do not advise swallowing clove oil or putting it in the mouth.
What clove oil is
Clove oil is an aromatic oil extracted from cloves, the spice. [4] A review names eugenyl acetate, eugenol and beta-caryophyllene as the most significant chemicals in clove oil. [5] Eugenol, the main one, is the chemical behind most clove-oil safety questions. Whole cloves as a food spice are covered in Cloves (herbs and botanicals) and whole spices as food. Results for the spice do not carry over to the concentrated oil.Which plant, which part
Clove oil comes from Syzygium aromaticum (L.) Merr. & L.M.Perry, the accepted name on GBIF, in the myrtle family (Myrtaceae). [6] The sources we read do not state which plant part the oil in each study came from, and they do not compare oils from different parts of the tree.Traditional use
Traditional use only, not proof. LiverTox, the US liver-injury database, describes eugenol (clove oil) as an herbal oil used on the skin around a toothache and, more rarely, taken by mouth for stomach and breathing complaints. [4] The sources we read give no region-specific history for clove oil.What research shows
| Use | What the source found | Strength of evidence | Population and form studied |
|---|---|---|---|
| Toothache and dental pain | A 2025 systematic review of 21 studies of plant-based dental pain relievers listed clove oil (eugenol) among the agents with the strongest analgesic properties, and said preparations need standardizing and larger trials are needed. [7] | Promising but limited | Mixed dental conditions; mixed preparations, reviewed together [7] |
| Needle pain before dental injections in children | In a pilot study of 90 children, those who had clove oil applied by clinicians before an injection reported the least pain of three groups. [8] | Preliminary; study design limits conclusions | 90 children in a dental clinic; clove oil applied in the clinic, compared with lidocaine gel and ice [8] |
| Infection, cancer, general health | Proper evidence not found for the oil in people. We searched PubMed for clove oil trials; a 2020 review of laboratory findings is not evidence of effect in people. [5] | Preclinical (cells or animals) | Not applicable |
Toothache is a dental problem. Pain that lasts needs a dentist, because the cause (infection, a cracked tooth) is not treated by a pain-relieving oil. Eugenol-containing dental products are a dental-care question for a dentist; we do not advise putting clove oil in the mouth, and these studies do not change that.
Forms, and why the form matters
Sources we read describe clove oil applied by clinicians, used as an herbal oil on skin, and in tiny amounts as a food flavoring. We give no dilution or amount. The study results above are for specific dental uses and do not apply to bottled oil used at home.Official statements
- LiverTox (US National Institutes of Health): high-dose ingestion of eugenol can cause severe liver injury. [4]
- Poison Control (US): call 1-800-222-1222 if an essential oil is swallowed. [3]
Frequently asked questions
Does clove oil cure a toothache?
No oil cures a toothache. A 2025 review suggested clove oil (eugenol) has pain-relieving properties in dental research, but called for standardized preparations and larger trials. [7] See a dentist for lasting pain.
Can children be harmed by clove oil?
Yes. Case reports describe liver failure in a 3-month-old and a 15-month-old after swallowing clove oil. [2][1] Keep it locked away and call Poison Help at 1-800-222-1222 after any swallowing.
Can clove oil cause an allergic reaction?
Yes. In a German patch-test series, 1.6% of 10,930 people tested reacted to clove oil. [10]
Is clove oil the same as eugenol?
Eugenol is the main chemical in clove oil, but the oil contains other chemicals too. [5]
Is clove oil safe in pregnancy?
Not described in the sources we read. Ask a clinician.
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Safety
- Swallowing, children. Besides the liver failure cases above, a 7-month-old developed central nervous system depression, urinary abnormalities and a large anion-gap acidosis (a blood chemistry imbalance) after accidental oral administration of clove oil, and recovered with supportive care. [9] A paper analyzing a national database reported a 14-fold increase in home accidents related to aromatherapy (all oils, not only clove) from 1994 to 1999. [1]
- Liver. LiverTox says eugenol in therapeutic doses has not been implicated in liver injury, but ingestion of high doses, as in an overdose, can cause severe liver injury. [4] See liver safety.
- Skin allergy. In a large German patch-test series of 10,930 people, 8.3% reacted to at least one of twelve essential oils, and clove oil caused 1.6% positive reactions. [10] A case report describes occupational allergic contact dermatitis from eugenol, oil of cinnamon and oil of cloves in a physiotherapist. [11] See strong oils and skin reactions.
- Mouth lining. A 2019 case report describes eugenol allergy mimicking recurrent mouth ulcers and burning mouth syndrome. [12]
- Skin and damaged skin. Poison Control advises not using essential oils on damaged skin. [3]
- Medicines, pregnancy, breastfeeding. Interactions with specific medicines and safety of the oil in pregnancy or breastfeeding are not described in the sources we read. Poison Control says essential oils may interact with medications. [3] See how interactions work and oils in pregnancy. The liver cases mean people with liver disease should ask a clinician before any use.
- Surgery: tell the surgical team about any oil product you use.
- Pets: the sources we read for this page do not cover cats and dogs; see essential oils and pets.
References
- Essential oil poisoning: N-acetylcysteine for eugenol-induced hepatic failure and analysis of a national database. Eur J Pediatr 2005. Read 2026-10-23.
- N-acetylcysteine for the treatment of clove oil-induced fulminant hepatic failure. J Toxicol Clin Toxicol 2004. Read 2026-10-23.
- Essential oils: Poisonous when misused (Poison Control). Read 2026-10-23.
- Eugenol (Clove Oil) (LiverTox, National Institutes of Health). Read 2026-10-23.
- Syzygium aromaticum L. (Myrtaceae): Traditional Uses, Bioactive Chemical Constituents, Pharmacological and Toxicological Activities. Biomolecules 2020. Read 2026-10-23.
- Syzygium aromaticum (L.) Merr. & L.M.Perry (GBIF Backbone Taxonomy). Read 2026-10-23.
- Analgesic Efficacy of Phytotherapeutic Agents in Dental Pain Management: A Systematic Review. Int J Dent 2025. Read 2026-10-23.
- An In Vivo Comparative Analysis of Pain Perception in Children Following Lidocaine Gel, Clove Oil, and Precooling for Intraoral Injections: A Pilot Study. Int J Clin Pediatr Dent 2024. Read 2026-10-23.
- Clove oil ingestion in an infant. Hum Exp Toxicol 1991. Read 2026-10-23.
- Contact sensitization to essential oils: IVDK data of the years 2010-2019. Contact Dermatitis 2022. Read 2026-10-23.
- Occupational allergic contact dermatitis from eugenol, oil of cinnamon and oil of cloves in a physiotherapist. Contact Dermatitis 1999. Read 2026-10-23.
- Eugenol allergy mimicking recurrent aphthous stomatitis and burning mouth syndrome. Contact Dermatitis 2019. Read 2026-10-23.