Can you have hepatitis B vaccine after infection?

Vaccination prepares the immune system to prevent a new hepatitis B infection. If the virus is already present, vaccination cannot clear it or repair liver inflammation. Blood tests can show whether infection is current, past, or absent and whether protective immunity is present. The result helps a clinician decide whether vaccination is useful and whether liver monitoring or specialist care is needed.

Some people with hepatitis B have no symptoms. Others develop fatigue, nausea, abdominal discomfort, yellowing of the skin, or dark urine. These signs can have several causes, so they should not be used to diagnose hepatitis B without testing.

Arrange a medical review and describe any prior diagnosis, exposure, vaccine doses, and available test results. Ask which hepatitis B blood tests are appropriate and whether a liver function test is needed. Avoid sharing razors, toothbrushes, needles, or other items that may carry blood. Cover open cuts, use protection during sex until a clinician advises otherwise, and tell household or sexual contacts to seek vaccination advice. Do not start or repeat a vaccine course without reviewing your results.

Seek urgent assessment for yellowing skin, severe abdominal pain, repeated vomiting, confusion, unusual sleepiness, bleeding, or rapidly worsening illness. Contact a healthcare service promptly after a new exposure even if you previously had hepatitis B, because the circumstances and test results affect the next step. Emergency symptoms after a vaccine, such as throat swelling or breathing difficulty, require immediate care.

Ask whether infection is current or past, whether vaccination offers any benefit, which tests are needed, how the liver will be monitored, and how to protect people who live with or have sex with you.