Immunoglobulin (also called gamma globulin or immune globulin) is a substance made from human blood plasma. The plasma, processed from donated human blood, contains antibodies that protect the body against diseases. When you are given an immunoglobulin, your body uses antibodies from other people’s blood plasma to help prevent illness. And even though immunoglobulins are obtained from blood, they are purified so that they can’t pass on diseases to the person who receives them.
Specific types of immunoglobulin are made to protect against specific diseases, such as hepatitis, chickenpox, or measles. Immunoglobulin injections may:
- Give short-term protection against or reduce the severity of certain diseases.
- Protect your fetus if you are pregnant and at risk for Rh sensitization.
- Decrease the immune system’s ability to attack body tissues in some cases of autoimmune disease.
- Help people who have an inherited problem making their own antibodies or those who are having treatment for certain types of cancer (such as leukemia). Treatments for some cancers can cause the body to stop producing its own antibodies, making immunoglobulin treatment necessary.
You may be given an immunoglobulin if you are exposed to certain infectious diseases, such as hepatitis A, rubella, or measles. The immunoglobulin may prevent or reduce the severity of the illness if given shortly after exposure. The time period during which an injection provides this benefit ranges from days to months, depending on the disease.
Immunoglobulins do not provide long-term protection in the same way as a traditional vaccine. The protection they provide is short-term, usually lasting a few months. It is still possible to get the disease after the immunoglobulin has worn off.