Whether or not tea tree oil is an effective remedy for cold sores depends in large part on the individual and the seriousness of his or her condition. There isn’t much formal research on this point at all, which makes it somewhat difficult to make generalized claims. Tea tree oil is usually considered to be an “alternative” medicine or a home remedy, and these sorts of cures aren’t typically subjected to the sort of rigorous testing and trials that more streamlined pharmaceuticals are. Just the same, many people claim that tea tree oil for a cold sore is more effective than traditional medicine. This may be because of the oil’s antiseptic properties. Many people also use it as a preventative measure in the hopes that it can ward off cold sores before they even appear.
Lack of Research
It is difficult to assess how effective tea tree oil is for healing a cold sore. Unlike traditional medications there are very few scientific studies that back up its effectiveness, and there is also a disparity in terms of oil strength and actual concentration. Most governments set up regulatory bodies to oversee how pharmaceutical drugs are produced, manufactured, and sold; some even regulate advertising. In the majority of cases these rules don’t apply to dietary supplements or “all natural” remedies like tea tree oil, though.
On one hand this means that not much is known about the oil’s clinical healing potential, and on the other it opens the possibility for a wide disparity of products being sold under the “tea tree oil” name in the marketplace. Different brands might have different formulations, and how one product works to combat something like a cold sore might not hold true for another oil from a distinct brand.
Reasons it Might Work
Alternative medicine practitioners often recommend tea tree oil for a cold sore, and many people say that it works really well. It is important to note that tea tree oil probably won't get rid of a cold sore immediately upon use, though; it is more likely to speed up the natural healing process, but this can still be helpful. A lot of this probably has to do with the antiseptic and healing properties of the oil.
Tea tree oil, which is sometimes also called “melaleuca oil,” comes from the Melaleuca alternifolia plant, and is naturally astringent. This means that it may be capable of sterilizing wounds, killing bacteria, and preventing the colonization or spread of new bacteria at the site. Cold sores are usually caused by the herpes simplex virus, which spreads easily but can also be fairly easily defeated by medications or other remedies. Though the healing properties of tea tree oil may be weak, they may be enough for cold sores in some cases. Cold sores usually heal on their own within a week or two, but with the oil this may be shortened to just a few days.
Tee tree oil is usually applied topically to cold sores, which means that it’s rubbed right onto the sore itself. People usually do this with a moistened cotton ball or cotton swab. Several applications throughout the day may help speed healing even further. It is important, however, to keep an eye out for skin irritation. If the skin exhibits signs of sensitivity — like redness or slight swelling — the oil should either be diluted or not used at all.
As a Preventative Measure
Some people also recommend using tea tree oil as a preventative measure rather than just to treat cold sores that have already formed. Regular use of a lip balm containing this compound, for example, may be an effective prophylaxis. While such a product is not guaranteed to work, many people attest to its effectiveness.