We investigated the effect of rifampin on pruritus in 12 patients with chronic liver disease: non-A, non-B hepatitis (n = 3), alcoholic cirrhosis (n = 4), primary biliary cirrhosis (n = 4), and primary sclerosing cholangitis (n = 1). The study was a crossover, randomized, double-blind trial where placebo and drug were given daily in identical capsules (300 mg) for 2 weeks each, with a 1 week washout before and after each cycle. Mean duration of pruritus was 1.6 years (range of 4 months-5 years). Blood tests were done weekly and patients used a visual analogue scale (VAS) from 0 to 100 to mark their level of itchiness daily. Only transaminases were significantly lower while the patients were on rifampin. VAS scores were minimally affected by either rifampin or placebo. At the end of the trial, four patients said they were less itchy on rifampin and three preferred placebo. Of these seven patients, small falls in VAS scores occurred in two patients on rifampin and two on placebo; there was no change in the remaining three. There was little change in serum bile salt levels during the trial. No patient became jaundiced and deepening of jaundice did not occur in the four patients with initially elevated bilirubin. We conclude that a daily 300 mg dose of rifampin was not effective in relieving pruritus in a variety of chronic liver diseases.