Tea tree oil, also called melaleuca oil, is distilled from the leaves of Melaleuca alternifolia. In addition to its antibacterial properties, it also has anti-inflammatory, antiviral, and antifungal effects. Taking tea tree essential oil internally is never a good idea. For almost 100 years, the oil has been used to treat skin conditions, particularly acne. This oil is currently used to treat a number of different ailments. Using tea tree oil, one can treat athlete's foot, and head lice.