The treatment of neurological autoimmune diseases with intravenous immunoglobulins (IVIG) seems succesful. Usually a daily dose of 0,4 g/kg body weight is given for 5 days. IVIG works in acute cases for only a limited period. It is not predictable whether a patient responds or not. Because of less side effects IVIG is useful for severe ill patients especially in septic complications. Some recent studies prooved antiidiotypic antibodies as the main therapeutic factor in IVIG. This immunosuppressive treatment is expensive. Further studies for dose finding, special indications, duration of treatment and cost benefit analysis are needed.