Ciclopirox Hydroxypropyl Chitosan (CPX‐HPCH) Nail Lacquer and Breathable Cosmetic Nail Polish: In Vitro Evaluation of Drug Transungual Permeation Following the Combined Application

Abstract

Background: Onychomycosis produces nail chromatic alterations that lead patients to mask them with cosmetic enamels. Objectives: Evaluate drug transungual permeation and antimycotic activity against selected strains after application of CPX‐HPCH nail lacquer (NL) on the nail pre‐covered with breathable cosmetic polish. Methods: CPX transungual permeation after applying CPX‐HPCH NL once or twice a day on bovine hoof membranes pre‐covered with a breathable cosmetic nail polish was compared to that obtained applying CPX‐HPCH NL directly on the membrane. The relevant experimental permeates underwent an in vitro susceptibility test. Results: After CPX‐HPCH NL application once a day, the drug transungual flux in the presence of cosmetic product tended to decrease while maintaining the antifungal activity. Two daily applications of CPX‐HPCH NL on the membrane pre‐covered with cosmetic polish exhibited the same permeation profile as daily application of the medicated lacquer directly on the nail as well as the same microbiological activity. Conclusions: The breathable cosmetic nail polish can be applied on the nail affected by onychomycosis in association with CPX‐HPCH NL to mask the imperfections. The application of CPX‐HPCH NL twice a day appears to be a good solution to obtain the same results as for a daily application without the presence of the cosmetic layer.