Formulation and evaluation of gel and emulgel of chili extract (Capsicum frutescens L.) as topical dosage forms

Capsaicinoid is used in topical treatment and high-dose dermal patch, to relieve the pain of peripheral neuropathy such as post-herpetic neuralgia. It may be used as cream for the temporary relief of minor aches and pains of muscles and joints associated with arthritis. The purpose of the present study was to measure penetration ability of capsaicinoid through Spraque-Dawley rat abdomen skin as membrane diffusion. Capsaicinoid had been extracted from chili fructus by reflux method and its content was determined. Capsaicinoid was used as an active ingredient in emulgel and gel formulation. The penetration of capsaicinoid from each dosage forms were evaluated using Franz diffusion cell with Spraque-Dawley rat abdomen skin as membrane. Physical stability of the products were investigated, including influence of temperatures, organoleptic test, pH, globule diameter, viscosity, and consistency. The result of the research showed, chili fructus extract is containing 1.93 ± 0.2 % capsaicinoid. Sum of cumulative penetration of capsaicinoid from gel and emulgel dosage forms were 153.11 ± 2.42 μg cm-², and 321.22 ± 4.67 μg cm-2, respectively. The percentage of penetrated capsaicinoid from gel and emulgel dosage forms were 19.39 ± 0.31 % and 40.69 ± 0.59 %, respectively. Flux of capsaicinoid from gel and emulgel dosage forms were 11.26 ± 0.20 μg cm-2 hour-1 and 24,28 ± 0,52 μg cm-2 hour-1, respectively. The results revealed that penetration ability of emulgel dosage form is higher than gel, and both of the dosage form is physically stable.