Herb library · Spice · Syzygium aromaticum (syn. Eugenia caryophyllus)
Cloves
The dried flower buds of an Indonesian tree, used whole and ground in cooking, and distilled into clove oil, an old toothache remedy. The European Medicines Agency accepts clove oil as a traditional herbal medicine for toothache and mild mouth and throat irritation. The oil is dangerous if swallowed: 5–10 ml (one or two teaspoons) has caused life-threatening poisoning in small children.
Serious warning
Clove OIL is poisonous if swallowed, especially by small children. The European Medicines Agency reports life-threatening poisoning in children under 2 after 5–10 ml, and case reports describe liver failure and bleeding problems in a 2-year-old. The spice in cooking amounts is not the concern.
Traditional use
Native to a few islands of the Moluccas, cloves were chewed at the Chinese court to sweeten the breath before speaking to the emperor, are named in the Sanskrit medical writer Charaka, and were known to early Arab and Greek writers. Dutt's 1877 compilation from Sanskrit medical works records that Hindu physicians counted cloves light and cooling and gave an infusion of them to ease thirst, and the Sushruta Samhita groups them with nutmeg and camphor as bitter, pungent spices that freshen the mouth.Chinese, Indian and European medicine used them for digestion, nausea and toothache. Today clove oil is sold for toothache and in mouthwashes, and the spice is used in cooking worldwide.
Traditional energetics
Galenic (hot or cold, dry or moist)
Hot and dry in the third degree. Culpeper's Complete Herbal (1814), p. 267 (opens in a new tab)
Ayurveda
Taste (rasa): bitter and pungent; in dosha theory it balances kapha. An English Translation of the Sushruta Samhita, vol. 1 (1907), Sutrasthanam, ch. XLVI, p. 507 (opens in a new tab)
Chinese materia medica
Temperature: warm. Chinese Materia Medica: Vegetable Kingdom (1911), p. 95 (opens in a new tab)
What studies show
- Limited
Numbing the mouth: in a 2006 trial in 73 adults, a homemade clove gel dulled the pain of a needle prick in the gum as well as benzocaine gel, and both did better than placebo. The EMA accepts clove oil for temporary toothache relief as a traditional use, based on long-standing use rather than trials.
- Limited
Mouthwash in intensive care: in a 2023 randomized trial of 168 patients on breathing machines, a clove-extract mouthwash was followed by fewer cases of ventilator-associated pneumonia than chlorhexidine. It is a single trial.
- Limited
Anal fissure: a single-blind randomized trial of 55 people found that more fissures closed with a 1% clove oil cream than with the usual stool softeners and numbing cream. It has not been confirmed in larger studies.
Be careful of
Cautions
- AmountFood amounts and the oil are very different. The EMA reports life-threatening poisoning in children under 2 who swallowed 5–10 ml of clove oil, and overdose can cause drowsiness, coma, seizures, low blood sugar and liver damage. Keep clove oil away from children.
- ConditionThe EMA does not recommend clove oil products for anyone under 18, and says toothache relief with clove oil is only a stopgap: see a dentist as soon as possible. Avoid getting the undiluted oil on the gums, and do not use it for more than a week.
- AllergyMouth irritation and allergic reactions have been reported with clove oil (EMA). Do not use it if you are allergic to cloves or to Peru balsam. Eugenol, the main compound, can irritate the mouth and cause allergic reactions when used in dental materials.
- PregnancyThe EMA says the safety of clove oil in pregnancy and breastfeeding has not been established and does not recommend it then. Cloves in food amounts are a different matter.
- Ask a clinicianTalk with a clinician or pharmacist before using this if you take prescription medicines, are pregnant or breastfeeding, or are giving it to a child.
From the old books
What herbals and dispensaries of the past printed. History, in their words.
“Cloves, as might be expected, are much used in Hindu Medicine, as an aromatic adjunct. They are regarded as light, cooling, stomachic, digestive and useful in thirst, vomiting, flatulence, colic, etc. An infusion of cloves is given to appease thirst.”
“Cloves appear to have been known in China as early as B.C 266. At that time it was customary for the officers of the court to hold the spice in the mouth before addressing the sovereign in order that their breath might have an agreeable odour.”
“Its use as a substitute for the crude drug, and especially its application to aching teeth, is well known and appreciated by the Chinese at the present time.”
Sources
- Community herbal monograph on Syzygium aromaticum (L.) Merill et L. M. Perry, floris aetheroleum (clove oil), EMA/HMPC/534924/2010 (opens in a new tab) · EMA · read September 25, 2026
- Caryophylli floris aetheroleum — herbal medicinal product (EMA) (opens in a new tab) · EMA · read September 25, 2026
- The effect of clove and benzocaine versus placebo as topical anesthetics (J Dent, 2006) — PubMed record (opens in a new tab) · NIH · read September 25, 2026
- Effect of clove mouthwash on the incidence of ventilator-associated pneumonia in intensive care unit patients (Clin Oral Investig, 2023) — PubMed record (opens in a new tab) · NIH · read September 25, 2026
- Clove oil cream: a new effective treatment for chronic anal fissure (Colorectal Dis, 2007) — PubMed record (opens in a new tab) · NIH · read September 25, 2026
- Disseminated intravascular coagulation and hepatocellular necrosis due to clove oil (Blood Coagul Fibrinolysis, 1992) — PubMed record (opens in a new tab) · NIH · read September 25, 2026
- Clove oil ingestion in an infant (Hum Exp Toxicol, 1991) — PubMed record (opens in a new tab) · NIH · read September 25, 2026
- Adverse reactions associated with the use of eugenol in dentistry (Br Dent J, 2002) — PubMed record (opens in a new tab) · NIH · read September 25, 2026
Reviewed September 25, 2026.