Sustained-release dosage form of phenylpropanolamine hydrochloride. Part II: Formulation and in vitro release kinetics from tableted microcapsules.

This work was planned to prepare sustained-action preparations of phenylpropanolamine hydrochloride by microencapsulation and by tableted microcapsules. Dissolution from both suspended microcapsules and the tablets was studied using the USP XXII basket method in simulated gastric and intestinal fluid without enzyme. The results were applied to zero-order, first-order, Hixson Crowell, RRSBW, Q/square root of t, (Bt)a and Higuchi kinetic models. Dissolution of PPA.HCl was found to be governed by the core:wall ratio, drug particle size, media pH and type of disintegrating agent. Dissolution kinetics were studied and evaluated.