Controlled drug permeation I: controlled release of butamben through silicone membrane by complexation

The effects of caffeine, beta-cyclodextrin, and povidone on the permeation behavior of butamben from saturated solutions in these complexing agents through a dimethyl polysiloxane membrane were investigated at 30 degrees. In all systems, these agents increased the rate of release over the plain saturated drug solution. The effect was more pronounced with caffeine and beta-cyclodextrin than with povidone. Interpretation of these results with the aid of solubility data for the corresponding systems led to the following generalization. For a fixed total (free and complexed) amount of drug available for release, sustained release is associated with systems containing more stable complexes. The practical value of this approach to the controlled release of drug is discussed.