Hepatitis B (HBsAg)
Screens for active Hepatitis B infection.
About this test
HBsAg looks for a hepatitis B surface protein that can indicate current infection.
Common reasons for testing
- Hepatitis B infection screening in pregnancy or another clinician-directed setting.
These are examples of clinical uses. Your history and symptoms determine whether testing is appropriate.
What to expect
A small blood sample is taken from a vein in your arm. You may feel a brief pinch and have mild bruising. Tell the person collecting your sample if you have fainted with needles or take a blood thinner; keep pressure on the site afterward.
Appointment length
Your visit is expected to take about 15 minutes at our West Ashley location.
Categories
Preparation
- Fasting is not usually needed for this test alone. If other tests are being collected, confirm their instructions before your visit.
- Bring a list of medicines and supplements, including biotin, vitamins, and hormones. Do not stop or change prescribed medicines unless your clinician tells you to.
Order requirement
No outside order needed
Understanding your results
- HBsAg alone does not establish immunity or distinguish every stage of infection.
- Initial adult screening commonly uses a three-test panel; confirm whether additional hepatitis B tests are needed.
What happens next?
Review the report with your clinician alongside your symptoms, medical history, and earlier results. A value outside the reference range does not always mean disease, and a normal result does not explain every symptom. Confirm who will arrange any repeat or additional testing.
Sources & further reading
This patient summary draws on published clinical literature and professional guidance. Patient resources are identified separately below. Preparation also depends on your specific order and the collecting laboratory or imaging team.
- Screening and Testing for Hepatitis B Virus Infection: CDC Recommendations
MMWR Recommendations and Reports, 2023
Content updated October 11, 2026. General education; individual advice comes from your care team.
Know the cost before your visit
Palmetto Preventive is a direct-pay service. You will see clear payment terms before your booking is finalized — no surprise lab bill.
Self-pay price
One transparent price for this test. Payment terms are presented before your booking is finalized.
Start bookingOur pricing promise
Transparent self-pay pricing — you see the price before you book.
No surprise lab bill after your visit.
If testing is not approved, your payment is refunded in full.
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Start the guided booking. It takes just a few minutes, and you can move back and forth without losing your answers.