Optimization of Sumatriptan Succinate Transdermal Emulgel For Treatment of Migraine

Abstract

Purpose: Sumatriptan succinate is a BCS class III drug. Oral administration of drug suffers from poor bioavailability problem due to pre-systemic metabolism. Bioavailability for oral route is 15%, for nasal route is 17% and for parenteral route is 97%. Substantial proportion of patients suffers from severe nausea or vomiting during their migraine attack, which make oral treatment unsatisfactory. Transdermal delivery will overcome the problems of the drug giving better results to patients suffering from migraine. Methods: Oleic acid, labrafil M 1994 and transcutol P was used as oil, surfactant and cosurfactant respectively. Both the oily and aqueous phases were heated separately. Oily phase were added to the aqueous phase. Mixing of gel and emulsion in ratio of 1:1 gave emulgel. Emulsion was evaluated for globule size, zeta potential, drug content, stability etc. Carbopol 934 and Xanthan gum was used as a gelling agent. Optimization was carried by factorial design. Emulgel was evaluated for physical parameters, viscosity, drug content, bioadhesive strength, spreadability, in-vitro and ex-vivo diffusion study. Results: FE-SEM image shown spherical globules in shape with size 51.40 µm. Zeta potential showed good stability of the emulsion. FTIR and DSC studies revealed that drug and all excipients were compatible. Factorial design gave batch F7 as optimized one. ANOVA results shown that drug release and gel viscosity values are strongly dependent on concentration of carbopol 934 and xanthan gum respectively. Ex-vivo diffusion study for batch F7 through goat skin indicated 88.68±2.52 % drug release. Statistical studies showed that drug release from the optimized formulation (F7) followed First order release kinetics. Conclusion: Sumatriptan succinate emulgel act as depot of drug which releases drug in controlled manner overcoming oral route side effects.