Development and Evaluation of Topical Drug Delivery System for Terbinafine Hydrochloride Using Niosomes

Fungal infection caused by fungus called dermatophyte infects top layer of skin, hair or nails. An allylamine antifungal agent terbinafine hydrochloride is used topically and orally. Its topical administration is preferred but barrier properties of stratum corneum decreases absorption and requires frequent application. It has low oral bioavailability due to hepatic first pass metabolism and many systemic adverse effects. Niosomes have been reported to enhance residence time of drugs in stratum corneum and epidermis, while reducing systemic absorption and improve penetration of entrapped drug across skin. Niosomes of terbinafine hydrochloride were prepared by film hydration method in size range of 0.24 to 9.4 m. Maximum entrapment efficiency was observed in formulation containing span 60 at 1:1 molar ratio of cholesterol and surfactant. Zeta potential values of niosomes containing span 60 (1:1) were more stable than other niosomal formulations. Niosomes were incorporated in 1.5 %w/v carbopol gel at pH 6.8-7.0. In in vitro antifungal study against candida albicans, vesicular systems were found to be more effective than conventional gel. The formulations containing tween 60 (1.5:1) and span 80 (1:1) were found to have maximum zone of inhibition. In ex vivo percutaneous permeation studies, niosomal formulations have shown superior skin penetration and drug deposition as compared to conventional formulation. The formulation containing tween 80 has shown higher drug deposition in rat skin as compared to other formulations. The niosomal vesicles can be used to enhance penetration and deposition of terbinafine hydrochloride in skin.