Inflammatory Myopathy.

Patients with polymyositis or dermatomyositis should be treated with prednisone (approximately 1 mg/kg/d) for an initial period of 4 to 6 weeks. Once improvement occurs, the dose should be tapered and converted to an alternate-day regimen, which should be continued for at least 12 months. Methotrexate or azathioprine should be administered concomitantly to patients in whom there is inadequate control. The early introduction of one of these drugs allows more rapid reduction in the dose of prednisone and helps to avert serious side effects. Intravenous immunoglobulin therapy is indicated for patients who have immunodeficiency, who are unable to tolerate immu-nosuppressive drugs, whose conditions are deteriorating, or who have severe relapses. Cyclosporine or cyclophosphamide may be effective for resistant disease. Patients with inclusion body myositis should undergo a 3- to 6-month trial of prednisone, alone or in combination with methotrexate or azathioprine. Maintenance doses of these drugs should be continued if the patient's condition improves or stabilizes.