Formulation and Evaluation of Peppermint Oil-Enriched Miconazole Cream for Enhanced Topical Antifungal Delivery

AbstractMiconazole nitrate is a widely used topical antifungal agent with limited aqueous solubility (BCS II), often resulting insuboptimal skin permeation and patient compliance. Incorporation of essential oils has emerged as a strategy to enhance drugsolubilization and skin penetration. This study aimed to develop and evaluate oil-in-water cream formulations of miconazolenitrate enriched with peppermint oil as a permeation enhancer, and to identify an optimized formulation based onphysicochemical and in vitro release characteristics. Five formulations (F1–F5) were prepared by the fusion method, varyingpeppermint oil (0.5–2.5% w/w) while maintaining constant Carbopol 934 and emulsifier levels. All batches were characterizedfor pH, viscosity (Brookfield rheometry), spreadability, drug content (UV spectrophotometry at 260 nm), and in vitro diffusionusing egg membrane in phosphate buffer pH 6.8. Data represent mean ± SD (n = 3). All formulations yielded homogeneouscreams with pH values between 6.2 and 6.8 and drug content ≥ 92%. Spreadability increased from 3.0 to 3.6 cm, whereasviscosity ranged from 18,000 to 19,500 cP with higher oil levels. Cumulative drug release at 8 h improved significantly withpeppermint oil concentration, peaking at 96.8% for F2 (1% oil). F2 exhibited an optimal balance of viscosity (18,200 cP),spreadability (3.4 cm), and sustained release. The peppermint oil-enriched miconazole cream (F2) demonstrated superiorphysicochemical properties and enhanced in vitro release, indicating its potential as a patient-friendly topical antifungalformulation. Further in vivo studies are warranted.