ABSTRACT:
Terbinafine hydrochloride is an allylamine antifungal agent used for dermatophytic infections, but conventional oral therapy may be associated with first-pass metabolism, gastrointestinal discomfort and systemic adverse effects, while conventional topical preparations may provide inadequate penetration into deeper skin layers. The present study aimed to formulate and evaluate matrix-type transdermal patches of terbinafine hydrochloride using hydroxypropyl methylcellulose E5 (HPMC E5) and polyvinyl alcohol (PVA), with clove oil as a natural permeation enhancer. Patches were prepared by the solvent casting method and optimized using a three-level factorial design in which HPMC E5 concentration and clove oil concentration were selected as independent variables, while drug release and skin permeation were selected as responses. The prepared patches were evaluated for appearance, thickness, folding endurance, drug content, moisture content, in vitro drug release, skin permeation and short-term stability. Preformulation studies confirmed the identity and suitability of the drug. FTIR and DSC studies indicated no major incompatibility between terbinafine hydrochloride and selected excipients. The optimized formulation F9, containing 800 mg HPMC E5 and 80 mL clove oil, showed excellent physical appearance, smooth surface, high flexibility, thickness of 0.30 mm, folding endurance of 298, drug content of 99.12%, and moisture content of 2.48%. F9 demonstrated the highest cumulative drug release of 91.05% at 8 h and maximum skin permeation of 78%. Stability testing for one month showed no significant changes in appearance, thickness, folding endurance, drug content or release behavior. The study indicates that clove-oil-enhanced terbinafine transdermal patches may be a promising approach for sustained antifungal therapy with improved patient compliance.