How Immune Globulin Works for Treating Viral Hepatitis

Immune globulin, also known as IG, is a remarkable type of immunization therapy. It's a substance that contains various antibodies collected from blood donors that can be used to protect someone from a particular disease. Since IG contains antibodies, it can help lessen the severity of a disease or even prevent it from developing.

Nurse preparing an injection
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How Does IG Work?

Blood is a complex, liquid-like substance made up of cells (red blood cells, white blood cells, and platelets) floating in a protein-rich fluid called "plasma," which contains important antibodies that protect against disease. IG is made from the plasma part of blood, which is collected from at least 1,000 donors to make sure the distribution of antibodies is complete. The plasma is purified, which makes it safe to use.

What's the Difference Between IG and Vaccine?

IG is a substance made up of antibodies that are naturally made by the body to provide protection from certain diseases. A vaccine is a substance made up of actual viruses or bacteria that stimulate the body to make more antibodies.

When you get a dose of IG, you're getting antibodies that are ready to immediately start working to defend your body. Vaccines, however, require actual inactivated viruses or bacteria to first stimulate your immune system to start producing its own antibodies. This explains why IG starts to work immediately and also why IG provides only a few months of protection (usually about three months), while vaccines take several weeks to become effective but provide protection for decades.

How Do I Receive IG?

Most IG is given as an intramuscular injection. It's a relatively thick fluid, so it's injected in a large muscle (usually in one of the buttocks for adults or in the front of a thigh for children). The shot is given by a nurse or a physician. However, it is not an absolute rule and intravenous administration of IG is also very common.

Is IG Safe?

Yes, IG is considered very safe, because serious reactions to a dose are very uncommon. Since IG is a thick fluid, it's usually a little painful during or after the injection, but this is a minor discomfort. Other common side effects are flushing, headache, chills, and nausea. Serious reactions may involve chest pain, breathing difficulty or anaphylaxis (a severe allergic reaction), but are extremely uncommon.

IG does not contain thimerosal (a mercury-based preservative) and is tested for blood-borne microbes, including syphilis, hepatitis B, hepatitis C, and HIV. Furthermore, the U.S. government requires manufacturers to follow significant safety procedures, which has ensured that IG doesn't spread diseases.

IG is safe for pregnant women and women who are breastfeeding.

However, it is not recommended for some people. This includes people with a history of serious reactions to IG.

Are There Different Types of IG?

Yes, in addition to regular IG, there is hyperimmune globulin, which is similar to regular immune globulin except that it has an abundance of a specific antibody instead of a distribution of a variety of antibodies. There is also IG especially prepared to be used intravenously called IGIV.

Is Viral Hepatitis Treated With IG?

Immune globulin is available to treat hepatitis A and hepatitis B.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Mayo Clinic. Drugs and Supplements. Hepatitis B Immunoglobulin.

  2. Centers for Disease Control. Immunization: You Call the Shots. Use of Immune Globulin.

  3. Guo Y, Tian X, Wang X, Xiao Z. Adverse Effects of Immunoglobulin Therapy. Front. Immunol. doi:10.3389/fimmu.2018.01299

  4. Drugs and Lactation Database (LactMed) [Internet]. Bethesda (MD): National Library of Medicine (US); 2006-. Immune Globulin.

  5. Centers for Disease Control and Prevention, Division of Viral Hepatitis, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention. Sources for IG and HBIG.

Additional Reading

By Charles Daniel
 Charles Daniel, MPH, CHES is an infectious disease epidemiologist, specializing in hepatitis.