The treatment with immunoglobulin (IgG) has led to the clinical improvement in all 12 patients with generalized myasthenia and practically has not caused any side-effects. The highest efficacy was seen in patients with a threat of or developed mixed crisis who received high doses of IgG (0,4-0,5 g per one kg of body mass) in the course of 3-5 intravenous drop introductions administered along with basic treatment with glucocorticoid and immunosuppressive drugs. In patients who received IgG once in smaller doses (0,2-0,3 g per one kg of body mass) to stabilize the disease course or to hasten recovery from the exacerbation, the clinical effect was similar though less prolonged. The treatment course with IgG stopped myasthenic crises in all cases. The clinical efficacy of IgG was not correlated with anti-acetylcholine receptor antibodies.