Sulconazole nitrate 1% cream applied twice daily was compared with its vehicle in the treatment of 229 patients with chronic moccasin-type tinea pedis confirmed by positive results of a potassium hydroxide preparation. At admission in this randomized, double-blind, parallel multicenter trial, 131 patients had positive dermatophyte cultures; Trichophyton rubrum was identified in 121 (92%). After 4 weeks of treatment, patients were examined and, if necessary, were treated for an additional 2 weeks. Sulconazole cream was significantly more effective than the vehicle in the treatment of chronic T. rubrum tinea pedis; 57% of patients were cured by sulconazole, compared with 13% cured with the vehicle. Relapse rates, assessed 2 weeks after the end of treatment, were significantly lower in patients treated with sulconazole than in those receiving vehicle (27% vs 71%). The 103 patients with moccasin-type tinea pedis whose cultures were not positive for T. rubrum achieved similar results.