Immunoglobulin G (IgG) in Serum, Mass Concentration

What Is Immunoglobulin G (IgG)?

IgG is the most common type of antibody in your blood. It’s produced by your immune system to fight off infections and helps your body remember past illnesses, providing long-term protection. These antibodies are crucial for defending against bacteria and viruses that enter your body through cuts, infections, or other entry points.

Why Might You Need This Test?

Your doctor may order an IgG test to check for low or high levels, which can indicate conditions like immune deficiencies, chronic infections, or certain autoimmune diseases. It’s also used in monitoring treatment responses for conditions like HIV, hepatitis, or certain cancers.

When Is an IgG Test Performed?

This test is often done as part of a general health check, to diagnose or monitor conditions affecting your immune system, or to evaluate symptoms like frequent infections, fatigue, or unexplained illnesses. It may also be used during pregnancy to assess maternal-fetal immunity.

What Does the Test Involve?

A blood sample is taken from a vein in your arm. The sample is sent to a lab, where it is analyzed to measure the amount of IgG antibodies present. The results help determine if your immune system is functioning normally or if there may be an underlying issue.