Tea tree oil, which is an essential oil extracted from a small Australian tree of the same name, is used in many cosmetic and health applications. The oil is naturally nontoxic, antifungal and antibacterial, and is effective against many infections. Its properties make it a popular treatment for dandruff and head lice. Adding tea tree oil to your hair-washing regimen can be done in minutes.
Use a dropper to add 10 drops of tea tree oil to 8 oz. of shampoo. This creates a 2 percent solution. You may increase the amount of oil you add up to 5 percent, but don't use more than that to prevent possible irritation. Add only 5 drops of oil to the shampoo if you are treating a child for head lice.
Mix the shampoo and oil together, and apply directly to the scalp. Massage into the skin with your fingertips. Let it sit on your head for five minutes.
Rinse hair thoroughly and style as usual.