ABSTRACT
In vitro-release profile of chlorphenesin from Eudragit films was investigated. As the hydrophilic polymer fractions, e.g. Eudragit RL 100, RLPM or L100 increased, the release rate of the drug from the matrix increased and the release pattern followed Higuchi model. Increasing drug concentration in the film also resulted in a considerable increase in the release rate of the drug. The release rate constant was found to be film thickness-independent, while the linear relationship between t0.5 and the square of film thickness confirmed the diffusion controlled profile. Incorporation of water- soluble and insoluble plasticizers affected the drug release rate to different extent, depending on the type and concentration of plasticizers. Increasing drug release rate from films due to plasticizers could be arranged as follows: Glycerol > glyceryl triacetate > PEG 400 > propylene glycol > dimethyl phthalate > diethyl phthalate. The effect of different enhancers on increasing drug release followed the order dimethyl sulfoxide > sodium lauryl sulfate > polyvinylpyrrolidine > Tween 80. Clinical evaluation of the selected formula was carried out on 20 patients and compared with an official cream. A complete cure of 70% of patients treated with films was an acceptable and promising result compared with 90% cure obtained with the cream