Terbinafine (Lamisil®) is a new fungicidal agent of the allylamine class of drugs that is available as an oral or topical (1% cream) treatment. A study was designed to assess the efficacy of the topical formulation, in patients who had tinea cruris/corporis, compared with placebo when used once daily for only 1 week. Follow-ups were at 2 and 4 weeks after treatment. At the end of follow-up (4 weeks), 84% and 12.5% of terbinafine- and placebo-treated patients, respectively, were completely (mycolog-ically and clinically) cured. Furthermore, side-effects were rarely reported during the study.