What should you know about human hepatitis B immunoglobulin?

This medicine is made from donated human plasma containing antibodies against hepatitis B. It may be considered after contact with infected blood or body fluids, or for a newborn when the birthing parent has hepatitis B. It does not treat an established hepatitis B infection and does not replace vaccination. Your clinician decides whether it is appropriate based on the type of exposure, timing, vaccination history and test results.

Some people have soreness, redness or swelling where it is injected. A mild headache or feeling unwell can occur. Tell the clinical team about previous reactions to immunoglobulin or blood products.

Seek medical advice promptly after a possible exposure, even if you feel well. Do not wait for symptoms such as dark urine or fatigue. Take any vaccination records and explain when and how the contact happened. You may be offered hepatitis B vaccination as well, because immunoglobulin gives short-term protection while vaccination helps the immune system build its own response. Follow the advised testing plan.

Get urgent help for trouble breathing, facial swelling, widespread hives, faintness or severe weakness after the injection. Contact a clinician for persistent vomiting, yellowing of the skin or eyes, worsening abdominal pain, or new dark urine. These symptoms need assessment and are not proof of a particular cause.

Ask whether you need immunoglobulin, vaccination, or both; what testing is planned; which side effects should prompt help; and when your follow-up results will be reviewed.