Immunoglobulin Replacement Therapy

When you need it—and when you don’t

Some people have frequent, severe infections because their bodies don’t make enough antibodies. Antibodies are proteins that the body produces to fight off harmful substances. For people who don’t produce enough antibodies, immunoglobulin (IgG) replacement therapy can be a lifesaver. But other people get the treatment even though they don’t need it. Here’s what you need to know.

IgG treatment can help people with PIDD.

PIDD stands for primary immunodeficiency disease. It usually appears in childhood, but can also appear in adulthood. It increases the risk of infections, like pneumonia and sinusitis. At least one person in 1,200 in the U.S. has PIDD.

People with PIDD lack antibodies, especially IgG.

IgG antibodies are the body’s main defense against bacterial infection. IgG treatment replaces these antibodies. It can stop or prevent most of their infections, but it doesn’t help most people with frequent infections.

IgG only helps people who lack the IgG antibody.

  • It won’t help you if your immune system already makes enough antibodies.
  • It isn’t helpful for every form of PIDD. It won’t help people who lack IgA, a different antibody.
  • It’s usually not needed if a person just has low IgG blood levels. Often, they still have enough antibodies to prevent infections or control them with the help of antibiotics.

IgG therapy has risks.

IgG antibodies are injected into a vein or under the skin. Both methods can cause side effects, although they are more common with vein injections. Side effects can include serious allergic reactions, kidney failure, and headache and flu-like symptoms. In rare cases, patients with severe headaches can have irritation of the lining around the brain. There can also be swelling, bruising, or infection at the injection site. Finally, the medicine is made from human blood, so it has a very small risk of carrying viruses.

IgG treatment can be costly.

The cost depends on your dose and body weight, and the injection method. Treatment can cost more than $30,000 a year. It must be repeated regularly, usually for life.

When is IgG treatment a good idea?

If you have severe, frequent, unusual, or persistent infections, talk to your doctor. Your doctor can order a series of tests to see if IgG
therapy might help you. First, you should have a blood test to check your antibody levels. Then, you will get one or more vaccines and another antibody test. If your body doesn’t make antibodies in response to vaccination, IgG treatment might be a good idea. It will help your doctor decide if IgG treatment may help reduce the frequency or severity of infections.

IgG treatment may also be helpful if:

  • You have very low blood levels of IgG.
  • You are diagnosed with certain immune disorders.

This report is for you to use when talking with your healthcare provider. It is not a substitute for medical advice and treatment. Use of this report is at your own risk.

© 2017 Consumer Reports. Developed in cooperation with the American Academy of Allergy, Asthma & Immunology