Terbinafine is an antifungal that is available in over-the-counter (OTC) medicines that treat symptoms associated with skin fungus infections such as athlete’s foot, jock itch, and ringworm. It may be written as terbinafine or terbinafine hydrochloride, but it is the same active ingredient. Terbinafine can be found in single-ingredient topical skin fungus medicines.
Terbinafine is approved by the U.S. Food and Drug Administration (FDA) and is safe and effective when used according to the Drug Facts label directions. Terbinafine-containing medicines should only be used on the outer surface of the body to treat skin fungus infections. These products are not intended to be used on the nails or the scalp.