PHARMACOKINETICS OF CONTROLLED RELEASE MORPHINE BY THE USE OF MORPHINE SULPHATE TABLETS (MST) IN PATIENTS WITH CANCER LIVER

Abstract

Summary and Conclusions This study has determined the kinetic profile of controlled release morphine (MST) 30 mg in fifteen patients with liver carcinoma. Eight patients were included because they had clinical, sonographic and CT findings of primary carcinoma on top of liver cirrhosis due to chronic hepatitis C . d Seven patients with metastatic liver cancer were also included. Their primary were; cancer bladder (four patients), retroperitoneal {one patient), cancer pylorus (one patient) and cancer pancreas (one patient). Ten healthy controls included were our Pain Clinic control for 30 mg MST, for comparison. Plasma drug concentrations were measured in venous blood samples at intervals up to 12 hours by high performance liquid chromatography (HPLC). The estimation of total body clearance Cl as well as systemic bioavailability were done using the compartmental 4 method. The serum concentration was higher at all sampling times in malignant patients with peak concentration Ca 52.7±1.9 ng/mL (primary liver cancer), Cm. 39.4±2.8 ng/mL in secondary metastatic liver cancer than control Ct 12.8±0.4 ng/mL. Ta also was significantly higher in malignant patients than controls. Systemic bioavailability was 4 fold higher in primary liver cancer, 3 fold in secondary metastatic than controls reflecting the same significant magnitude in AUC