Pruritus in chronic liver disease: mechanisms and treatment.

Pruritus is a complication of liver disease. It can have a marked negative impact on quality of life; when intractable, it is an indication for liver transplantation. The cause of this type of pruritus is unknown. There is, however, evidence to suggest that the pruritus associated with liver disease is mediated, at least in part, by endogenous opioids. A central mechanism has been proposed. Therapeutic interventions have concentrated on the removal of presumed and unknown pruritogens from the circulation, hepatic enzyme induction, and, over the past decade, opiate antagonists, the first specific treatment for the pruritus of cholestasis. Other pharmacologic interventions that change neurotransmission have recently been reported to decrease the pruritus in patients with liver disease, as has a newly developed system that applies albumin-based dialysis. These interventions are promising, but they must be tested in properly controlled behavioral trials.