EVALUATION OF THE CORRELATION BETWEEN INVIVO AND INVITRO RELEASE OF PHENYLPROPANOLAMINE HCL FROM CONTROLLED-RELEASE TABLETS

The dissolution behavior of two controlled-release matrix tablets, formualtions A and B, containing phenylpropanolamine HCl as a model drug was studied using a paddle method and a paddle-beads procedure. The paddle-beads method involves a system in which polystyrene beads are inserted into the dissolution medium to cause mechanical destruction or frictional force. These tablets have the advantages of pH- and agitation-independent release performance in vitro using the paddle method. These matrices and solution were orally administered to six beagle dogs, and the results were analyzed by deconvolution. In vitro dissolution curves using the paddle method did not coincide with the in vivo profiles in the fasted condition, while in vitro release using the paddle-beads method was similar to the in vivo profile in the fasted condition in dogs. The paddle-beads method may be useful for investigating in vivo/in vitro correlation of controlled-release dosage forms.