Deflazacort is a new glucocorticoid which in previous studies was found to be about 0.8 times as potent as prednisone. Twelve outpatients affected by chronic idiopathic thrombocytopenic purpura, in whom the maintenance dose of corticosteroid had already been established, were given 6 mg deflazacort for each 5 mg prednisone equivalent. Effectiveness of deflazacort therapy was estimated on the basis of the results of platelet count, bleeding time, tourniquet test, and physical signs related to platelet function. Tolerability was evaluated on the basis of laboratory data, side effects, and body weight. Deflazacort was administered for 54--263 days (mean 114.5) and, at the same mean daily dose of prednisone, succeeded in keeping platelet number unchanged. As far as bleeding time, tourniquet test, and physical signs are concerned, deflazacort therapy gave a further improvement compared to prednisone. Both treatments were very well tolerated. The high number of white blood cells and neutrophils during prednisone therapy was restored to the normal range by deflazacort
