A randomized comparison of nail surface remanence of three nail lacquers, containing amorolfine 5%, ciclopirox 8% or tioconazole 28%, in healthy volunteers.

This randomized, investigator-masked study compared the remanence on the nail surface of commercially available antimycotic nail lacquers containing amorolfine, ciclopirox and tioconazole. The lacquers, to which a coloring agent was added, were applied randomly to the left and right thumbnails and great toenails of 10 healthy volunteers. Volunteers were asked to wash their hands under standardized conditions at 30, 60 and 90 min after product application and to take at least one shower during the study. Photographs were taken immediately after drug application and at 30, 60 and 90 min, i.e., immediately after each hand washing, and then at 8 and 24 h. Photographs of treated toenails were taken at 0, 8 and 24 h. Photographic image analysis allowed automatic calculation of the proportion of nail surface remaining covered by the different nail lacquers over time and after washing. In addition, clinical visual assessment was made to determine the degree of the nail surface covered by the nail lacquers over time. It was demonstrated that at 24 h after product application, remanence of amorolfine nail lacquer on the thumbnails was significantly higher than that of ciclopirox (p < 0.05) and that of tioconazole on the thumb- and toenails at each time point up to 8 h after product application (all p < 0.05). Clinical observation showed that 30 min after application, the tioconazole nail lacquer had still had not completely dried. Amorolfine nail lacquer was shown to be more resistant than ciclopirox and tioconazole nail lacquers to chemical trauma from soaps and to mechanical aggressions from the immediate nail environment.