Treatment of pityriasis versicolor with bifonazole shampoo: a randomized double-blind study

The application of a shampoo containing an antifungal agent is a convenient and useful means of treating pityriasis versicolor. The effect of bifonazole 1% shampoo on extensive pityriasis versicolor was assessed, and the optimal duration of treatment determined. A total of 30 patients with a diagnosis of pityriasis versicolor were allocated to one of three treatment groups (n = 10 each): (A) 2 days of bifonazole shampoo followed by 5 days of the vehicle only; (B) 7 days of bifonazole shampoo only; (C) 7 days of the vehicle only. Patients were seen after 1 and 6 weeks. Some of those showing no response after 1 week were treated 'openly' for 1 week with bifonazole shampoo. Four patients were lost to follow-up. After the first week, clinical and mycological cure was observed in ten patients, four (44%) in group A and six (75%) in group B, and an improvement in four patients, two in both group A and group B. Failure was seen in three group A patients and in all group C patients. Seven failed patients underwent 'open' treatment with bifonazole shampoo; after 1 week, six were cured and one showed no improvement. Two patients (one each from group A and group C) complained of a mild reversible pruritus. These findings indicate that bifonazole shampoo is significantly more effective than placebo in treating pityriasis versicolor; 7 days of treatment are preferable to 2 days.