Pruritus can be a debilitating symptom in patients with chronic cholestasis. Based on previous reports of its efficacy, we evaluated the impact of rifampin on the pruritus associated with primary biliary cirrhosis. Fourteen patients were included in a randomized, crossover study. After a 15-day washout period, subjects were followed for three weeks. During the first and third week, patients received 600 mg of rifampin or placebo; no treatment was administered during the second week. Pruritus was subjectively scored on a scale from 0 to 100. With rifampin, pruritus disappeared in 11 patients and partially improved in three; with placebo, only two had a partial response (P<0.001). six="" patients="" with="" a="" prior="" poor="" or="" no="" response="" to="" cholestyramine="" improved="" with="" rifampin.="" no="" changes="" in="" biochemical="" tests="" or="" side="" effects="" were="" observed="" during="" this="" period.="" we="" conclude="" that="" short-term="" administration="" of="" rifampin="" relieves="" pruritus="" in="" primary="" biliary="" cirrhosis.="" when="" administered="" over="" a="" period="" of="" eight="" months="" in="" an="" open="" study,="" the="" relief="" of="" pruritus="" was="" maintained,="" while="" one="" individual="" developed="" an="" allergic="" reaction.="" rifampin="" appears="" to="" be="" a="" safe="" drug="" in="" the="" management="" of="" the="" pruritus="" of="" primary="" biliary="">