Release of a drug from homogeneous ointments containing the drug in solution

The rate of release of resorcinol (5%) from hydrogels (Carbopol, sodium carboxymethylcellulose, starch), lipogels (alcoholic-base, esteric-bases containing different amounts of beeswax with and without a spreading additive, respectively) and Labrafils has been examined. For the experimental design adopted the release of the drug is linear between 10 and 70% of the amount of drug released. The results agree well with the mathematical model postulated by Higuchi (1962) for the release of a drug from homogeneous ointments containing the drug in solution.