When rats given D-galactosamine are then treated with the glucogenic amino acid alanine, their alanine aminotransferase (ALT) activity, total bilirubin level, and survival rate improve compared with when other amino acids are used. Here, we report a preliminary study of the clinical and pharmacological effects of alanine given to three patients with primary biliary cirrhosis (PBC). The patients were jaundiced and were in the end-stage of the disease. The treatment they had been receiving was continued while they were given 18 g of alanine per day for a planned 8 weeks. For all three patients, test results for total bilirubin, alkaline phosphatase, and ALT decreased by 25% or more from the base line at some time during treatment. The arterial ketone-body ratio increased. Two of the patients reported that their itching and fatigue lessened. Except for one patient given a second course, who reported nausea, adverse effects were not found. In end-stage PBC, alanine administration decreased the total bilirubin level and improved symptoms, so this compound may decrease jaundice in this disease. A long-term study of a larger group of patients is needed.