Clove Oil

Clove is one of the few remedies where the traditional record and the products on the shelf still match, but choosing the right form matters. These are the questions our naturopaths ask in store.

A good fit if

• You want short-term relief for an aching tooth while you wait for a dental appointment
• You're buying clove bud oil rather than leaf or stem oil, and you'll put it on the tooth
• You cook with it and want a jar that still has its flavour
• You're comfortable with a traditional-use basis rather than settled science

Check with us first if

• You take warfarin, aspirin, clopidogrel or any other blood thinner. In the lab, clove oil stops platelets clumping together, and it may add to bleeding risk.
• You have surgery or a tooth extraction coming up, for the same reason. Tell your surgeon or dentist as well.
• You take phenytoin for epilepsy. Clove may falsely raise measured phenytoin levels, which could lead to the wrong dose being chosen.
• Your skin reacts to fragrances or essential oils. Clove is a known skin sensitiser, and reactions mostly come from undiluted or high-strength oil.
• You were planning to put it on your gum. The European guidance is to apply the oil to the tooth and avoid your gum, because concentrated clove oil irritates the lining of your mouth.

• Whole dried clove bud (Schedule 1 item 1487). Best known for: Cooking, and the traditional digestive brew. Absorption: No Schedule 1 conditions at all, so no warnings and no container rules. Typical use: The spice itself, with 15 to 17% volatile oil still held inside the bud.
• Ground clove powder (item 1490). Best known for: Baking, and digestive formulas in capsules. Absorption: Also free of conditions in Schedule 1. Typical use: The same material with more surface area, so the oil goes stale faster. It's the form most people buy and the one with no human trial.
• Clove bud oil (item 1486). Best known for: Use on the teeth and in the mouth, and the form the evidence is based on. Absorption: Steam-distilled from the dried bud, with 75 to 88% eugenol. Typical use: The preparation named in the EU traditional monograph. Above 25% total clove oils it must carry 'Not to be taken'.
• Clove leaf oil and clove stem oil (items 1488 and 1491). Best known for: Aroma and flavour. Absorption: Distilled from the leaf or stem, with a different mix of minor compounds. Typical use: Harsher. Neither has a traditional monograph or a human trial behind it, and the 25% cap counts all three oils together.
• Clove extract mouth rinse. Best known for: Plaque and gum research. Absorption: A water-based extract rather than an oil. Typical use: A 6.66% rinse was tested twice daily for five days in hospital patients on ventilators, against chlorhexidine. That's a clinical setting, not a shelf product.
• Standardised polyphenol bud extract. Best known for: The antioxidant research, which is one small trial. Absorption: A water-soluble powder, standardised for polyphenols rather than oil. Typical use: 250 mg a day in a 16-person crossover trial. Different chemistry from clove oil, one branded ingredient and one research group.
• Isolated eugenol (item 2149). Best known for: Dental cements and flavouring. Absorption: The main clove compound, purified. Typical use: Can't be an active in an Australian listed medicine, and products taken by mouth cap it at 0.06% of the formula.
• Clove oil terpenes (item 1489). Best known for: Flavour only. Absorption: A terpene portion, not the whole oil. Typical use: Allowed only as a flavour combined with other ingredients, with total flavour no more than 5%.

Reference values. There's no recommended intake for clove. It's a spice and a herb rather than a nutrient, so the NHMRC values don't cover it.

Typical supplemental range. The traditional European directions are written for the oil, not a capsule. For the mouth: 'Mouth washes corresponding to 1–5% essential oil. Apply several times daily.' For a tooth: 'Undiluted essential oil or solutions in a strength of minimum 50% or gels in a strength of 20%. Repeat administration after 20 minutes, then every 2 hours if necessary.' The only swallowed dose tested in people is 250 mg a day of a standardised polyphenol bud extract, in a trial of 16 men.

Upper level. Both traditional European uses carry the same limit: 'Not to be used for more than 1 week'. Australia limits the product rather than the dose. Above 25% total clove oils, the container must hold no more than 25 mL and have a restricted flow insert, and clove oil for use in the mouth 'may not contain more than 5 millilitres of the oil or distillate' at no more than 25%.

Worth knowing. Clove in cooking is food, and none of the medicine rules apply. If you're using the oil, put it on the tooth, not the gum, and for no more than a week. What you need depends on your age, diet and health, so talk to one of our naturopaths.

Food first, where the diet allows it.

• Whole buds in slow cooking: stocks, curries, braises, mulled drinks: A few buds to a pot. The dried bud runs 15 to 17% essential oil
• Ground clove in baking: gingerbread is the traditional European use of the spice
• A decoction of the bud: the traditional European preparation for dyspeptic complaints, flatulence and diarrhoea
• Clove tincture: very dilute next to the oil: about 0.039% eugenol

If any of these sound like you, talk to one of our naturopaths or your doctor before you start.

• Swallowing clove oil is the serious risk, and above all it's a child safety problem. A 7-month-old who swallowed one teaspoon developed CNS depression, metabolic acidosis, protein and ketones in the urine, and spent four days in hospital. Two 2-year-old boys who each drank 5 to 10 mL went into a deep coma with severe acidosis, seizures, badly impaired liver function and a serious clotting disorder (disseminated intravascular coagulopathy). All three recovered. Keep clove oil out of reach.
• You take an anticoagulant or antiplatelet medicine, such as warfarin, aspirin or clopidogrel. In the lab, clove oil reduced platelet clumping triggered by arachidonic acid, epinephrine and collagen, and this effect may increase bleeding risk alongside those medicines. Talk to your prescriber.
• You have surgery or a tooth extraction coming up. The same platelet finding applies. Stop well beforehand and tell your surgeon.
• You take phenytoin. Clove may cause a falsely high phenytoin blood test result, which can lead to the wrong dose being chosen.
• You're pregnant or breastfeeding. Safety hasn't been established, and without enough data it isn't recommended.
• Children and teenagers under 18. Use hasn't been established because there isn't enough data.
• You're allergic to Peru balsam. This is a stated reason not to use it, along with allergy to clove itself. People sensitised to Peru balsam reacted at concentrations above 0.12% in petrolatum.
• You have contact allergies. Clove is one of nine essential oils with over 2% positive patch-test reactions in people with dermatitis, often alongside reactions to the fragrance mix. Most reactions follow pure oils or high-strength products, and neat clove oil is treated as an irritant to skin, eyes and airways as well as a skin sensitiser.
• You're prone to irritation in your mouth. Concentrated clove oil may irritate the lining of the mouth, which is why the monograph applies it to the tooth and says to avoid the gum.
• You'd use it for more than a week. 'Not to be used for more than 1 week' applies to both European traditional uses.
• You have epilepsy. Essential oils as a group include some that may reduce seizures and some that may trigger them. Clove and eugenol sit in the possibly seizure-reducing group, but no human trial settles which way it goes. Get advice first.