OBJECTIVE To evaluate the analgesic and side effects of controlled release morphine sulfate (MST) administered rectally and orally in patients with moderate and severe cancer pain.

Aim: To compare the clinical analgesic efficacy of controlled-release morphine tablets and patient-controlled intravenous analgesia in late stage cancer patients.

The present study was done both in vivo by cannulating pancreatic duct of morphine dependent rats and in vitro using perfused pancreatic slices from morphine dependent rats.