Evaluation of Essential Oils as Natural Permeation Enhancers for the Topical Delivery of Synthetic Drugs

Introduction: The effect of essential oils such as Anise oil, Basil oil, Hempseed oil, and Sage oil on the permeation of ketoconazole, a BCS class II drug, through rat skin has been investigated, as these essential oils are less explored for topical application. Ketoconazole was selected as a model drug since it is commonly used in topical formulations. Material and Methods: The permeation study was performed on rat skin by using a Franz Diffu-sion apparatus, and the histopathological assessment was also carried out. Results: In Study 1, the highest flux and enhancement ratio were achieved with 0.5% Anise Oil, yielding values of 0.23 mg/cm²/h and 5.04, respectively. In Study 2, the highest flux and enhance-ment ratio were achieved with 0.5% Sage Oil, yielding values of 0.26 mg/cm²/h and 5.73, respec-tively. Discussion: The findings of the above study demonstrate that it is possible to achieve enhanced flux via utilizing the proposed essential oils. Almost all of the essential oils did not produce any kind of skin irritation, making them suitable permeation enhancers for further investigation and utilization. Histopathological evaluation suggested no harmful effect on the tissues. Conclusion: The different properties and components of these essential oils could possibly be explored for future formulation developments for ketoconazole and ketoconazole-like drugs.