Efficacy of a piroctone olamine/climbazol shampoo in comparison with a zinc pyrithione shampoo in subjects with moderate to severe dandruff

Synopsis Dandruff is a chronic scalp disorder characterized by scaling and itching. A successful anti‐dandruff shampoo not only has to provide superior anti‐dandruff relief to ensure patient compliance. It also needs to offer excellent cosmetic and hair conditioning benefits at the same time. In this study, the efficacy of a shampoo containing 0.5% piroctone olamine and 0.45% climbazole (shampoo 1) was compared with a widely available commercial shampoo containing 1% zinc pyrithione (shampoo 2). In vitro studies investigating the anti‐mycotic efficacy of a combination of 0.5% piroctone olamine and 0.45% climbazole as well as 1% zinc pyrithione were performed. To study substantivity, pig skin punches were used as a model system and a test of wet combability was performed to characterize combing ease. In vivo home‐in‐use studies were carried out to determine the efficacy of both shampoos to improve scalp condition and reduce itching in subjects suffering from moderate to severe dandruff. Results demonstrated a comparable anti‐fungal effectiveness for 0.5% piroctone olamine plus 0.45% climbazole and 1% zinc pyrithione, respectively. Shampoo 1 showed a significantly higher anti‐mycotics substantivity compared to shampoo 2. After treatment with shampoo 1, the wet combing force was significantly reduced compared with shampoo 2, suggesting a better combability following the use of shampoo 1. In an in vivo split head design study, shampoo 1 was shown to be equally effective in reducing the amount of dandruff on the scalp compared with shampoo 2. The approval rate of volunteers regarding the question ‘The use of this shampoo decreases the itching of my scalp?’ after a 4‐week treatment with shampoo 1 equaled 90%. Overall, the shampoo formulation with 0.5% piroctone olamine and 0.45% climbazole effectively reduces the amount of dandruff and, at the same time, provides hair conditioning advantages.