Relationship of in Vitro Release to Urinary Recovery in Man of a Sustained-Release Preparation of S35 Prochlorperazine

A sustained-release preparation of S 35 -labeled prochlorperazine prepared with different in vitro release patterns as determined by the rotating bottle method was administered to human subjects. Urinary recovery of S 35 was determined by liquid scintillation counting. Previously published data on sustained-release preparations of phenylpropanolamine and trimeprazine, treated in the same fashion as the prochlorperazine data, are included. For the specific dosage form of each drug, a direct rank relationship was found to exist between in vitro data and the respective in vivo data.