Immunoglobulin (IgG) Replacement Therapy Defined

Immunoglobulin G (IgG) is one kind of antibody found in blood plasma. People suffering from immunodeficiency diseases involving poor IgG levels and/or function often benefit from a medical treatment called immunoglobulin replacement therapy, also known as IVIg or SCIg.

IgG is a blood product derived from blood donors. The IgG is purified from the rest of the blood through a processing system that safely eliminates potential infectious agents. 

The IgG can be given through an IV each month, or under the skin, (subcutaneous, SCIg) once a week or every two weeks. Both methods are effective at replacing IgG to levels necessary to fight infections. Each method has pros and cons that should be discussed with your allergist / immunologist.  

IgG replacement therapy is generally well tolerated, although side effects such as allergic reactions and headaches can occur.

Learn more about primary immunodeficiency diseases (PIDD) symptoms, diagnosis, treatment and management.

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