In treating tinea cruris, the use of corticosteroids in combination with antifungal agents to facilitate symptomatic relief is viewed by some practitioners as controversial, because the immunosuppressive activity of corticosteroids may compromise the management of the disease and elimination of the causative pathogen by the antifungal agent. In a randomized, single-blind multicenter parallel-group study in 198 patients with culture-confirmed tinea cruris, a 2-week course of Lotrisone (clotrimazole 1%/betamethasone dipropionate 0.05% cream) compared with Nizoral (ketoconazole 2% cream) showed that the combination of betamethasone dipropionate with clotrimazole provides effective disease management, with relief of signs and symptoms of the disease occurring early in therapy. Improvement in disease signs and symptoms (investigator-rated) and global response to treatment (investigator-rated) favored Lotrisone compared with Nizoral from day 2 up to the end of treatment on day 15 (P0.014). Results at the end of the study (day 29) showed Lotrisone and Nizoral to be equally effective: negative mycology in 85.0% of Lotrisone-treated patients vs 83.7% of Nizoral-treated patients (P= 0.845). Thus, betamethasone dipropionate in the combination did not compromise the ability of clotrimazole to eliminate the causative pathogen from patients with tinea cruris. Both treatments were well tolerated. Treatment-related adverse events occurred in 7.8% of Lotrisone-treated patients and in 10.7% of Nizoral-treated patients. Application site reactions, paresthesia, and pruritis were the most frequently reported events considered possibly or probably related to treatment. These tended to be mild, and none required discontinuation of treatment.