Immunoglobulin G (IgG ) Therapy
Immunoglobulins, such as immunoglobulin G (IgG), are part of your body’s immune system. Immunoglobulins respond to infections and regulate immune function. There are five classes of immunoglobulins: IgA, IgD, IgE, IgG, and IgM. IgG therapy is a blood product containing IgG that is used to treat certain immune deficiencies, autoimmune diseases, and acute infections.
What is IgG? IgG, which is sometimes called gamma globulin, is a blood product extracted from the pooled blood of thousands of blood donors. The final product is sterile, purified IgG that can be administered into a vein (intravenously) or under the skin (subcutaneously). IgG is sometimes called IVIG when it’s given intravenously or SCIG when given subcutaneously.
Which conditions does IgG treat?
he U.S. Food and Drug Administration (FDA) approves of IgG for several indications, such as:
• Bone marrow transplant (to prevent graft vs. host disease) • Chronic B-cell lymphocytic leukemia • HIV in children • Idiopathic thrombocytopenia • Kawasaki disease • Primary immunodeficiencies
IgG may also be prescribed by your physician for numerous other conditions, including:
• Autoimmune Diabetic Neuropathy • Chronic Inflammatory Demyelinating Polyneuropathy • Common Variable Immunodeficiency • Dermatomyositis • Guillain-Barre Syndrome • Hypogammaglobulinemia • Multifocal Motor Neuropathy • Multiple Sclerosis • Myasthenia Gravis • Polymyositis • Rheumatoid Arthritis • Severe Combined Immunodeficiency • Systemic Lupus Erythematosus • Wiskott-Aldrich Syndrome • X-Linked Agammaglobulinemia
How does IgG work?
Immunoglobulins are a type of protein known as antibodies. Antibodies help your body fight off disease-causing germs. IgG antibodies detect and bind to bacteria, viruses, and fungi in the bloodstream. Once the antibody is bound to the germ, white blood cells can come and destroy it.
IgG not only fights infection; it can also help control the symptoms of other diseases. IgG therapy is useful when a person’s body does not make enough IgG or in certain cases when a temporary boost can help treat a disease.
How often will I need IgG treatment?
Unfortunately, IgG is not a cure for any condition, rather it is a treatment. This means if your health improves after IgG therapy then you will generally require additional, on-going treatments. Depending on your disease, the effects of IgG therapy last from two weeks to three months. Your specific dosage and frequency of IgG administration will depend on your disease.
If you have a primary immune deficiency, you will likely require IgG treatments for life, while someone with an autoimmune condition may only use this therapy for months or years.
How is IgG provided as a therapy?
When IgG was first used as a therapy many decades ago, it was injected into the muscle. While this was effective for treatment, it could be quite painful for patients. Today IgG is given in one of two ways. First, it can be infused through a vein, which is called intravenous therapy. Second, it can be infused just under the skin, which is called subcutaneous therapy.
Intravenous IgG will be infused slowly over the course of several hours. The length of time can depend on your condition, how much IgG is prescribed, and your reaction to the treatment. This is generally done at an infusion center.
If you are prescribed subcutaneous IgG, you can learn how to do it yourself at home.
What side effects can I expect?
Patient tolerability of IgG therapy has improved over the years with better understanding of selecting the appropriate dose and rate of administration for each individual patient.
Common and minor side effects from IgG therapy include flu-like symptoms such as:
• Headache • Fever • Chills • Flushing • Nausea • Muscle aches
These flu-like symptoms can be minimized by drinking plenty of fluids before, during, and after infusion. It also helps to infuse IgG very slowly (that is, over a longer time period). Pain relieving medications and rest can also help with these minor symptoms. Some patients benefit from additional medications before IgG therapy, such as antihistamines, antiemetics, sedatives, antipyretics, and hydration solutions.
Although it is rare, there are also some serious symptoms that can occur with IgG therapy. These serious reactions include kidney failure, aseptic meningitis, anaphylaxis, blood clots, or stroke.
Is IgG therapy safe?
Although IgG is a blood product, the FDA considers the risk of transmission of infection from IgG to be extremely low. IgG manufacturers all adhere to strict safety standards to greatly reduce the risk of infection from IgG. All blood donors are screened and their blood is treated to destroy any viruses that might be present.
About my Condition
Where can I get more information?
Immune Deficiency Foundation www.primaryimmune.org
Primary Immunodeficiency Resource Center www.jmfworld.com
American Academy of Allergy, Asthma, and Immunology www.aaaai.org