Immunoglobulins are an important component of the immune system and of the host defense against infection. They are also important in immune regulation. The intravenous immunoglobulins has been proven beneficial in prophylaxis and treatment of infections in patients with primary and secondary immunodeficiency. Many studies confirmed the efficacy of IVIG in the treatment of idiopathic thrombocytopenic purpura and other autoimmune disorders. In the last years monoclonal antibodies were included to anticancer therapy in children and adults.