What should you know about hepatitis B card test?

The card uses a small blood sample to look for a marker associated with hepatitis B infection. A non-reactive result makes the marker less likely to be present, although your clinician may recommend another test if exposure was recent or symptoms and medical history raise concern.

A reactive screening result does not by itself show whether infection is recent, ongoing, or resolved. Laboratory testing can examine several hepatitis B markers and may be paired with a liver function test to understand whether the liver is under strain. Hepatitis B can occur without obvious symptoms; fatigue or dark urine should be discussed with a clinician, especially alongside yellowing of the skin or eyes.

Keep the test result and ask which laboratory tests are needed. Until the result is clarified, do not donate blood and avoid sharing razors, toothbrushes, or items that may carry blood. Use condoms and tell a healthcare professional about possible household or sexual exposure so contacts can receive appropriate advice.

A clinician can review vaccination history, previous results, medicines, and liver health. If you are not immune, hepatitis B vaccination may be discussed. Follow-up differs for each person, so take any arranged blood test even when you feel well.

Arrange prompt medical review after a reactive card test, a recent exposure, or symptoms such as dark urine, pale stools, yellow skin or eyes, marked fatigue, vomiting, or pain beneath the right ribs. Seek urgent help if confusion, extreme sleepiness, bleeding, or rapidly worsening jaundice develops. These symptoms need assessment because liver inflammation can have causes other than hepatitis B.

Ask: Which hepatitis B marker did the card test detect? Do I need confirmatory blood tests? Could the timing of a possible exposure affect the result? Should I have a liver function test or repeat testing? Do people close to me need testing or vaccination?