The efficacy of ketoconazole, a new oral antimycotic agent, was evaluated in an open trial. Forty-two nonpregant women were selected on the basis of proven vulvovaginal candidosis and were divided into two groups. One group received 400 mg of ketoconazole per day for three days, and the other group received 200 mg per day for three days. Of the 26 patients who received the 4OO-mg dosage, 24 were cured; of the 16 patients who received the 200-mg dosage, nine were cured. No adverse effects attributable to the drug were found.