Encephalopathy morphine

In a controlled trial involving eight decompensated cirrhotic patients (compared to six cancer patients with normal liver/kidney function), the half-life of morphine was increased and the clearance was reduced. The differences were statistically significant. Patients in this trial were administered a single dose of 4 mg FV morphine and, on a separate occasion, a single dose of 10 mg oral morphine. All patients had a history of encephalopathy, six had ascites, and two had oesophageal varices. There were many inadequacies in this trial one patient only received 5 mg oral morphine one received the IV dose but not the oral dose one did not receive the IV dose and the control group was administered 20 mg oral morphine rather than 10 mg [59]. 

Increased sensitivity to drugs is also encountered in liver disease. The use of anticoagulants increases the risk of bleeding due to the reduced absorption of vitamin K or decreased production of vitamin K-dependent clotting factors. There is an enhanced risk for respiratory depression and hepatic encephalopathy due to morphine or barbiturates in patients with severe liver disease. Vigorous use of diuretics can precipitate hepatic coma due to potassium loss in liver disease. There is an increased risk of hypoglycemia with... 

Acute encephalopathy with typical signs of morphine intoxication occurred in a patient taking aldesleukin (129). 

Eran A, Barak M. Posterior reversible encephalopathy syndrome after combined general and spinal anesthesia with intrathecal morphine. Anesth Analg 2009 108 (2) 609-12. 

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