Terbinafine

Terbinafine, sold under the brand name Lamisil among others, is an antifungal medication used to treat pityriasis versicolor, fungal nail infections, and ringworm including jock itch and athlete's foot. It is either taken by mouth or applied to the skin as a cream or ointment. Common side effects when taken by mouth include nausea, diarrhea, headache, cough, rash, and elevated liver enzymes. Severe side effects include liver problems and allergic reactions. Liver injury is, however, unusual. Oral use during pregnancy is not typically recommended. The cream and ointment may result in itchiness but are generally well tolerated. Terbinafine is in the allylamines family of medications. It works by decreasing the ability of fungi to synthesize ergosterol. It appears to result in fungal cell death. Terbinafine was discovered in 1991. It is on the World Health Organization's List of Essential Medicines. In 2023, it was the 253rd most commonly prescribed medication in the United States, with more than 1 million prescriptions.