 - Has impaired liver function e.g., alanine aminotransferase ALT 3 times the upper limit of normal ULN, or bilirubin 3 times ULN, known active hepatic disease e.g., hepatitis, evidence of clinically significant chronic liver disease or other condition affecting the liver e.g., chronic hepatitis that may suggest the potential for an increased susceptibility to hepatic toxicity with oral morphine exposure. Subjects with no previous history of liver function impairment may be enrolled prior to receipt of screening laboratory testing results. 