Dermatopharmacology of ciclopirox nail lacquer topical solution 8% in the treatment of onychomycosis

Ciclopirox is a synthetic hydroxypyridone antifungal agent. In contrast to the azoles, glucuronidation is the main metabolic pathway of ciclopirox; th erefore interactions with drugs metabolized via the cytochrome P-450 system are unlikely Ciclopirox is also distinct from the common systemic agents, which interfere with sterol biosynthesis. In fact, ciclopirox chelates triv alent cations (such as Fe3+), inhibits metal-dependent enzymes that are res ponsible for degradation of toxic metabolites in the fungal cells, and targ ets diverse metabolic leg, respiratory) and energy producing processes in m icrobial cells. Ciclopirox is a broad spectrum antimicrobial with activity against all the usual dermatophytes as well as yeast and nondermatophyte mo lds. It has demonstrated activity against gram positive and negative bacter ia, including resistant strains of Staphylococcus aureus. Ciclopirox exhibi ts fungal inhibitory activity (minimum inhibitory concentration < 4 mu g/mL for dermatophytes) as well as Fungicidal activity; to date resistance to t he drug has not been identified. Ciclopirox has been formulated in a nail l acquer delivery system. After evaporation of volatile solvents in the lacqu er, the concentration of ciclopirox in the remaining lacquer film reaches a pproximately 35%, providing a high concentration gradient for penetration i nto the nail. Radiolabel data demonstrate penetration into infected nails a fter only 1 application of the lacquer. Ciclopirox nail lacquer is a topica l product that provides an active fungicidal agent in a delivery system cap able of promoting nail penetration. With repeated applications, the antifun gal agent is homogeneously distributed through all layers of the toenail ac hieving concentrations of ciclopirox in er;cess of inhibitory and fungicida l concentrations for most pathogens. Although ciclopirox readily penetrates nails, very low levels of ciclopirox are recoverable systemically even aft er chronic use. Ciclopirox nail lacquer 8% is a topical product that provid es an active fungicidal agent in a delivery system capable of penetrating n ails.