Hepatitis associated with terbinafine therapy: three case reports and a review of the literature.

Terbinafine is an allylamine antifungal agent first launched in the USA in May 1996 with an estimated 7.5 million individuals worldwide having used the drug. Given orally it is effective for the treatment of dermatophyte infections and is prescribed predominantly for the superficial mycoses. Adverse effects have been reported in 46.7% of patients receiving the oral drug (compared with 29.2% receiving placebo, the attributable risk to terbinafine being 17.5%). Thus, oral terbinafine is associated with the rare development of symptomatic idiosyncratic hepatobiliary dysfunction (1:45,000-1:54,000) and we now describe three patients who developed this disorder whilst taking the medication. The hepatitis produced has the features of both hepatocellular necrosis (with elevations of hepatic enzyme concentrations) and cholestatic injury (with elevations of alkaline phosphatase and cholesterol levels), the latency period between the start of medication and the development of liver injury being approximately 4-6 weeks. The US terbinafine product monograph recommends that serum hepatic enzymes should be assessed in individuals receiving terbinafine for more than 6 weeks, as a result of which some physicians monitor these values at baseline and at 4-6 weeks.