Intravenous gamma globulin treatment is used to lower the risk of infection in those with a weakened immune system. It is also used to increase the blood count (platelets) in those suffering from idiopathic thrombocytopenia purpura, a blood disorder, states WebMD.
IVIG has antibodies called IgG, immunoglobulins, that target and destroy pathogens found in the bloodstream. These antibodies are pooled from the blood products of many blood donors so as to ensure a wide variety of antibodies, reports the Immune Deficiency Foundation.
IVIG also treats chronic fatigue syndrome and fibromyalgia, states Mayo Clinic. Gamma globulin therapy is administered intramuscularly or intravenously, reports the Immune Deficiency Foundation.