Pharmacokinetics of controlled release morphine (MST) in patients with liver carcinoma.
BACKGROUND
There are no studies reported on the pharmacokinetics of controlled release morphine (MST) in patients with hepatocellular carcinoma, the fifth most common cancer in the world.


METHODS
We have studied the pharmacokinetic profile of MST (30 mg) in 15 patients with liver carcinoma (eight with primary carcinoma on top of chronic hepatitis C, and seven with secondary metastatic liver malignancy as a result of other primary) compared with our previously published data for 10 healthy controls. Plasma morphine concentrations were measured in venous blood samples at intervals up to 12 h by high-pressure liquid chromatography. Total body clearance (Cl) and systemic bioavailability were estimated using a compartmental method.


RESULTS
Morphine bioavailability showed a substantial increase in patients with primary liver and secondary metastatic carcinoma than that of controls (64.8, 62.1, and 16.8%, respectively). The area under the serum concentration-time curve increased 4-fold in primary carcinoma (416 [sem25] microg h(-1) litre(-1)) and 3-fold (303 [21] microg h(-1) litre(-1)) in metastatic liver patients compared with healthy control (92.5 [3] microg h(-1) litre(-1)). No significant difference was found in T(max) between the two malignant groups but C(max) was significantly greater in primary liver carcinoma patients. Impaired morphine elimination was noted in primary carcinoma only (t(1/2) 5.99 [0.39] h).


CONCLUSIONS
Careful administration of morphine is recommended in patients with liver cancer.
Kotb
H I M
HI
Department of Anesthesia, Faculty of Medicine, Assiut University, Assiut, Egypt. kotbhi@yahoo.com
El-Kady
S A
SA
Emara
S E S
SE
Fouad
E A
EA
El-Kabsh
M Y
MY
D000328:Adult; D000368:Aged; D000701:Analgesics, Opioid / Q000097:blood* / Q000493:pharmacokinetics; D001682:Biological Availability; D006528:Carcinoma, Hepatocellular / Q000097:blood* / Q000503:physiopathology / Q000556:secondary; D003692:Delayed-Action Preparations; D006207:Half-Life; D019698:Hepatitis C, Chronic / Q000150:complications; D006801:Humans; D008099:Liver / Q000503:physiopathology; D008113:Liver Neoplasms / Q000097:blood* / Q000503:physiopathology / Q000556:secondary; D008875:Middle Aged; D009020:Morphine / Q000097:blood* / Q000493:pharmacokinetics; D010147:Pain Measurement; D017060:Patient Satisfaction
D000701:Analgesics, Opioid; D003692:Delayed-Action Preparations; D009020:Morphine