Indications for corticotropin therapy for multiple sclerosis, are steadily progressive disease or exacerbations lasting six months without remission. Definite contraindications are diabetes, psychosis, tuberculosis or other serious infection, severe hypertension, and active ulcers. Relative contraindications include prediabetic state, past ulcers, slight hypertension or osteoporosis, severe neurosis or depression. Successful management is possible in these cases, however. Serious complications in 47 cases during intensive treatment were psychoses, five; ulcers, three; septicemia, two; pathological fracture, one; adrenal exhaustion, one. Corticotropin therapy was discontinued in five patients because of psychoses, three; perforated ulcers, two. There was one death from septicemia. Serious complications in 41 cases during maintenance treatment (maximum four years) were osteoporosis, two; adrenal exhaustion, three; steroid diabetes, one; septicemia, one; ulcers, two. Corticotropin therapy was discontinued in three patients because of osteoporosis, one; septicemia, one; perforated ulcer, one. There was one death from steroid diabetes.