Known interactions

No interactions found.

Application of Oleum Melaleucae

Scientific Name: Tea Tree Oil

Other Names: Melaleuca Oil, Oleum Melaleucae, TTO

Who is this for?

Note: Taking tea tree oil by mouth may cause possibly serious side effects such as confusion, loss of muscle control, or coma. Even small amounts of tea tree oil may be harmful if swallowed by young children or household pets. Using tea tree oil orally is not recommended due to these risks.

Tea tree oil is applied topically as an anti-infective agent. It has been shown effective for bacterial infections (such as acne), fungal infections (such as athlete's foot), and viral infections (such as cold sores). It contains chemicals known as terpenes, which may damage or kill infectious organisms, while having little or no negative effect on bacteria that normally live on the skin. Because tea tree oil is generally non-irritating, it is also used to relieve mild burns, insect bites, sunburn, and other relatively minor skin conditions. In dentistry, tea tree oil has been used to kill bacteria in the mouth before dental surgery and to relieve mouth soreness caused by dental procedures. It has also been included in vaginal suppositories to treat vaginal infections. Steam produced when tea tree oil is added to boiling water, nebulizers, or hot baths may be inhaled to relieve nose, throat, and lung irritation. In studies of patients who suffered from oral candidiasis, a fungal infection of the mouth and throat, mouth rinses containing tea tree oil have shown some effectiveness in reducing symptoms. It may also be included in dandruff shampoos.

When should I be careful taking it?

Due to possible toxic effects, taking tea tree oil by mouth is not recommended. One case of coma has been attributed to taking approximately 4 ounces (one-half cup) of tea tree oil by mouth. Another case involved an adult who developed a rash and a significant increase in white blood cells after taking a small amount of tea tree oil by mouth. In another report, a small child who swallowed about 2 teaspoons of tea tree oil showed signs of drowsiness and the inability to coordinate muscle movement. All these individuals recovered completely.

Some reliable evidence associates decreased or lost hearing with the use of 100% tea tree oil in the ear. Therefore, tree oil preparations should not be put into the ears.


While tea tree oil is usually mild, several cases have been reported of individuals who developed itchy skin rashes from using tea tree oil or from handling parts of tea trees. Because tea trees contain chemicals similar to those found in the pine tree family, individuals who are sensitive to pine needles or resin may also be sensitive to tea tree oil.

What side effects should I watch for?

Side effects reported from the use of tea tree oil on the skin are generally mild and temporary at the site of application. They include:

  • Burning
  • Dryness
  • Irritation
  • Itching
  • Redness
  • Stinging

What interactions should I watch for?

No interactions have been identified between tea tree oil and prescription drugs, non-prescription drugs, other herbal products or foods. However, not all interactions may be known.

Some interactions between herbal products and medications can be more severe than others. The best way for you to avoid harmful interactions is to tell your doctor and/or pharmacist what medications you are currently taking, including any over-the-counter products, vitamins, and herbals.

Should I take it?

A number of different trees and bushes that grow in the islands of the south Pacific are known by the name "tea tree" because their bark, leaves, or twigs were used by native people or visiting sailors to make tea substitutes. Australian tea trees — the source of commercial tea tree oil — are really evergreen shrubs that grow in the swampy coastal areas of Australia. They grow relatively quickly, reaching 7 or 8 feet in height at maturity. Australian tea trees have soft, thick, light-colored bark. The sweet-smelling, fluffy white flowers that bloom in the summer are followed by seed pods that may take more than a year to mature. For commercial production or tea tree oil, new trees usually are sprouted from cuttings.

The pine-needle-like tea tree leaves are collected all during the year and distilled with steam. The resulting light yellow oil smells similar to nutmeg. Due to its pleasant odor and its antiseptic properties, tea tree oil may be included in cosmetic products, shampoos, and soaps. Because tea tree oil may kill many infective bacteria and fungi, it has also been used as a disinfectant for various types of industrial equipment and heating and cooling pipes. It has also been added to machine oils in industries, such as ship building, in which a high number of minor injuries occur among workers. Adding tea tree oil to the machine oils is thought to help prevent infections that may result because of the injuries.

Dosage and Administration

The concentration of tea tree oil in various commercial preparations ranges from about 1% to 100%. Often, the stronger products are used for hard-to-treat infections such as toenail fungus, while 5% to 10% tea tree oil gels have been used successfully to treat acne.

Commonly used dosages and durations include:

  • For fungal infections of fingernails or toenails: 100% tea tree oil twice a day for 6 months
  • For athlete's foot: 10% tea tree oil twice a day for one month
  • For acne: 5% tea tree oil once a day indefinitely
  • For oral candidiasis: one tablespoonful of 5% tea tree oil solution as a mouth wash that is held in the mouth and then spit out four times a day for up to 4 weeks


Tea tree oil may be applied to the skin as an antiseptic. Its anti-infective properties may treat conditions such as acne, athlete's foot, oral candidiasis, and vaginal infections. It may also soothe the irritation of non-infectious conditions such as sunburn.


Tea tree oil should not be taken by mouth due to possible toxicity. It should not be used in the ears because it may cause hearing loss. In addition, individuals who are sensitive to tea tree and who touch tea trees or who use tea tree oil may develop an allergic rash.

Side Effects

Topical tea tree oil may produce temporary dryness, itching, redness, or stinging at the application site.

If tea tree oil is taken by mouth, possible side effects include:

  • Rash
  • Confusion
  • Drowsiness
  • Loss of muscle coordination
  • Coma


No interactions have been identified between tea tree oil and prescription drugs, non-prescription drugs, other herbal products or foods. However, not all interactions may be known.


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(Note: The above information is not intended to replace the advice of your physician, pharmacist, or other healthcare professional. It is not meant to indicate that the use of the product is safe, appropriate, or effective for you.)

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