Hepatitis B vaccine !
Recombinant hepatitis B surface antigen (HBsAg) made in yeast. It prevents chronic hepatitis B and, with it, cirrhosis and liver cancer.
Updated 2026-11-01
Also called: HepB vaccine, Recombinant HBsAg vaccine, Pentavalent / hexavalent (combinations)
The figure shows HBsAg assembled into a recombinant spherical subviral particle, the same kind of non-infectious particle the vaccine contains.
Mechanism of action
The vaccine contains only the surface protein of the virus, with no viral DNA, so it cannot cause infection. HBsAg self-assembles into particles that the immune system recognises; B cells make anti-HBs antibodies that block the virus from entering liver cells. The younger a person is when infected, the more likely the infection becomes chronic, which is why vaccination starts at birth.
- Recombinant HBsAg particles are injected
- Helper T cells and B cells respond to the antigen
- Anti-HBs antibodies and memory cells form
- Anti-HBs blocks the virus before it reaches liver cells
Pharmacokinetics
- Onset and duration
- Protection follows the full series; anti-HBs is measured only in risk groups, after the last dose
Indications
- Prevention of hepatitis B from birth, including the birth dose Viral hepatitis →
- Indirect prevention of HBV-related liver cancer Hepatocellular carcinoma →
- Unvaccinated adolescents and adults at risk: health workers, dialysis, HIV, sex partners of HBsAg-positive people
Adverse effects
Common
- Pain at the injection site
- Low-grade fever
- Redness, swelling, headache
Contraindications
- Severe allergic reaction to a previous dose or a component
- Hypersensitivity to yeast
Key interactions
- Hepatitis B immunoglobulin (HBIG)
- Complementary: newborns of HBsAg-positive mothers receive vaccine and HBIG soon after birth, at separate injection sites
What is monitored
- Post-vaccination anti-HBs in risk groups (infants of HBsAg-positive mothers, health workers, dialysis, immunosuppressed); a low level leads to revaccination
- Mother's HBsAg status at delivery
Administration and safety
- Intramuscular route; in adults the deltoid
- Infants of HBsAg-positive mothers: vaccine and HBIG at different sites
- Check whether the product is single-antigen or part of a combination (pentavalent, hexavalent) before giving
- Record the batch and the product
Nursing care
- Check the mother's HBsAg result before the newborn's first dose
- Check the vaccination card and history of reactions or yeast allergy
- Watch for allergic reactions after the dose
- Explain that the vaccine contains no virus and cannot cause hepatitis
Pregnancy and breastfeeding
Pregnancy is not a contraindication to hepatitis B vaccination.
Test yourself
Think of the answer, then tap the question to see it.
Which serological marker shows immunity from vaccination alone?
Anti-HBs positive with anti-HBc negative: the vaccine contains only surface antigen, so it produces no anti-HBc.
Why is the first dose given at birth?
Infection acquired as an infant becomes chronic in most cases (up to about nine in ten), compared with about one in twenty adults.
What does a newborn of an HBsAg-positive mother receive?
Hepatitis B vaccine plus hepatitis B immunoglobulin soon after birth, at different injection sites.
Related drugs
Related conditions
← Back to the class: Viral vaccines
Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.
Sources: Chapter 10: Hepatitis B | Pink Book | CDC (Centers for Disease Control and Prevention, 2021); ATCDDD - ATC/DDD Index (WHO Collaborating Centre for Drug Statistics Methodology, 2026); Structure of HBV surface antigen determined in recombinant spherical subviral particle (RCSB Protein Data Bank, 2025).
Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake
Representative model, for educational purposes only.