What Is Immune Globulin?

A patient's quick reference to immunotherapy

Immune globulin (Ig) is the general term used for replacement therapy. It can be administered intravenously (IV) or subcutaneously (SQ). Immune globulin is derived from pooled plasma from carefully screened human donors and processed using rigorous purification steps. It is used to treat a variety of ailments both on and off-label.


Q: How is Ig made?

A: There is a highly specialized and lengthy process used to manufacture Ig. It begins in blood centers across the country where tens of thousands of healthy individuals donate their plasma (the portion of the blood where the immune globulins and other blood proteins are contained). The plasma from all of these individuals is then pooled together, and then chemically treated to isolate the immune globulins and remove any other blood proteins or blood-borne pathogens. The end result is a highly purified immune globulin preparation that is then packaged and ready to be infused.2

Q: Is Ig safe?

A: Yes! Since Ig is derived from human plasma, theoretically there is a risk of viral transmission; however, every possible precaution and step is taken to ensure patient safety. The blood centers are strictly monitored and regulated by the FDA and the manufacturers of Ig, as well as the individual donors, undergo an in-depth screening process to determine that they have not been exposed to certain pathogens, such as the HIV or hepatitis virus. Furthermore, during the manufacturing process, viral inactivation and removal steps are taken as an extra precaution.3

Q: How does Ig work?

A: For patients who are unable to produce their own antibodies, Ig is used to temporarily provide these patients with the antibodies they need to ward off infection. In patients with autoimmune diseases, or other conditions where the body's immune system is not functioning as it should, Ig can help regulate an overactive immune system by signaling it to slow down or stop inflammatory processes.4 It has also been hypothesized that Ig might redirect the out-of-control immune system from the body's tissues by serving as a target for the auto-antibodies. While it is possible to debate the mechanisms by which Ig successfully treats diseases, there is no denying its efficacy; Ig has significantly improved the quality of life for many individuals.5

Q: Why do I have to have regular infusions?

A: Ig increases the antibody level within your body. Antibodies, whether those produced naturally by your body or those administered IV or SQ, are eventually metabolized and eliminated by your body, usually in about 3-4 weeks for IV or anywhere from daily to monthly for SQ. Regular infusions are necessary to maintain immune globulin levels within the desired range.

Q: What kinds of side effects can I expect?

A: The most common side effects include headache, nausea, low-grade fever, chills, rash, neck/back stiffness, and fatigue. Generally, these side effects are mild and tolerable and most often, they can be alleviated by decreasing the rate of infusion. Administration of immunoglobulin subcutaneously (SCIG) is equally effective in preventing infections and has a lower incidence of serious adverse effects compared to IVIG.8 More serious side effects, such as allergic reactions, are rare, but have been reported. Should you develop an allergic reaction, your health care providers are sufficiently trained to handle this. Do not hesitate to contact your physician if your side effects are severe or persistent. It is possible to reduce the severity of the side effects associated with Ig infusions. Your physician may suggest premedication with acetaminophen or antihistamines; corticosteroids are also an option your doctor might conside.2 It is also important to make sure that you are sufficiently hydrated before your infusions. Make sure that you are drinking plenty of water for several days before your infusion.6

Q: Are there different brands of Ig? How are they different?

A: Currently there are several brands of Ig available in the United States. They are all essentially therapeutically equivalent, however they do differ from each other in terms of sugar, sodium, and antibody content, as well as the presence of preservatives or latex. Your physician will examine all of these factors and identify the best brand for you.7

1 BDI Pharma, Inc. Feb 2009. BDI Pharma, Inc. Clinical Glossary. 15 May 2009. http://www.bdipharma.com/clinical-glossary-I.aspx.
2 Immune Deficiency Foundation.IDF Patient and Family Handbook: For Primary Immunodeficiency Disease, 4th Edition. Towson, MD. 2007.
3 Immune Deficiency Foundation. How to Keep an Infusion Log. Towson, MD.
4 Talecris Biotherapeutics, Inc. The Gamunex Patient Handbook: A Q & A Resource. Research Triangle Park, NC. 2009.
5 Lockshin, MD, Michael and Lawrence J. Kagen, MD. Guidelines for Safe Use of IVIG (Intravenous Immunoglobulin). Hospital for Special Surgery, New York. 2003.
6 IVIG Therapy. 2009. American Outcomes Management. 18 May 2009. http://www.americanoutcomes.com/ivig-therapy-faq.php
7 Is IVIG Therapy Right for Me?. 2008. Baxter Healthcare Corporation. 15 May 2009. http://www.immunediseases.com/patients-and-families/ivig-therapy/is-ivig...
8 Subcutaneous Immunoglobulin Therapy: A new option for patients with primary immunodeficiency diseases. US National Library of Medicine. Published August 24, 2012. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3430092/