Formulation and permeability evaluation of Aloe vera gel containing Acyclovir

Background (including purposes): Acyclovir (ACV) is a widely-used drug in the prevention and specific treatment of diseases caused by Herpes virus. However, due to its limited solubility and poor permeability, its therapeutic effectiveness is not high. Therefore, improving the transdermal permeability of ACV is necessary to increase the therapeutic effect of the drug for topical administration. Materials and methods: The study investigated the effect of the concentration of gelling agent, and the concentration of Aloe vera (A.vera) on the physico-chemical properties, especially the in vitro and ex vivo permeability by using Franz diffusion cells. Results: The formulation with 5% (w/w) of ACV, 4.5% (w/w) of A.vera, 5% (w/w) of glycerin and 2% (w/w) of HPMC K100M had the physico-chemical properties suitable for topical administration and the best permeability enhancement as compared to other formulations with different concentrations of A.vera, and a commercial cream formulation containing 5% (w/w) of ACV. Conclusion: A.vera in the gel form was successful prepared and applied to increase the permeability of ACV. This A.vera gel has the potential to develop the formulations for transdermal administration Key words: Acyclovir, Aloe vera, permeability enhancement