Hepatitis B core antibody, immunoglobulin G (IgG) – Serum

What Does This Test Measure?

The test detects IgG antibodies produced by your immune system in response to the hepatitis B core antigen. Unlike IgM antibodies, which appear early in infection, IgG antibodies can persist for years, even after the acute infection has resolved. This test is often used to confirm past HBV exposure or monitor chronic infection.

Why Might You Need This Test?

Your healthcare provider may order this test if you have risk factors for hepatitis B (e.g., exposure to infected blood, travel to high-risk regions, or history of unprotected sex), if you have symptoms of liver disease, or as part of routine monitoring for chronic hepatitis B.

What to Expect Before the Test

No special preparation is needed. You’ll have a small needle inserted into your arm to draw a blood sample. The process is quick and typically painless. If you’re on blood-thinning medication, let your provider know before the test.

What to Expect After the Test

You may experience mild bruising, soreness, or swelling at the injection site. Apply gentle pressure to the area to help stop any bleeding. Avoid vigorous activity for a few hours. If you experience severe pain, excessive bleeding, or signs of infection (e.g., increased redness, fever), contact your provider.