High single-dose alternate-day corticosteroid regimens in treatment of polymyositis.

High single-dose alternate-day prednisolone therapy (ADT) was compared with daily-dose prednisolone therapy (DDT) for treatment of polymyositis. Thirty patients with polymyositis were treated with ADT for an average of 33.9 months. The combined number of improvements was 21 out of 30, a response rate of 70%. Side-effects were very rare and mild. On the other hand, 9 of 17 patients treated with DDT for an average 18.5 months improved, a response rate of 53%. The incidence of side-effects was strikingly higher than with ADT. ADT is therefore strongly advocated for treatment of polymyositis to avoid infectious complications and lessen cushingoid side-effects.