IG stands for immune globulin; it is a sterile solution of concentrated antibodies extracted from healthy donors which is administered into a vein. IG is used to treat disorders of the immune system or to boost immune response to serious illness, and to treat immuno-suppressed recipients of bone marrow transplants.1 Antibodies are responsible for defending our bodies from pathogens, such as viruses and bacteria.
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 
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
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, IVIG 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
IG does not affect your immune system’s ability to produce immune globulins; it simply increases the antibody level within your body. Antibodies whether those produced naturally by your body or those infused in the form of IG are eventually metabolized and eliminated by your body, usually in about 3-4 weeks. Regular infusions are necessary to maintain immune globulin levels within the desired range.2
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. 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 consider.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

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-right-for-me.html