Hepatitis B immunoglobulin (HBIG)

How it works

It supplies preformed human anti-hepatitis B surface antibodies that bind and neutralise circulating virus, giving temporary protection until active immunity develops.

Prescribing in practice

• It must be given as soon as possible after exposure because efficacy falls rapidly with delay, and it should be administered alongside, but at a separate injection site from, active hepatitis B vaccine.
• As a human plasma-derived product it carries the theoretical residual risk of transmissible agents, and IgA-deficient patients may react to trace IgA.
• Neonatal post-exposure prophylaxis requires HBIG combined with timely active vaccination per the immunisation schedule.

Monitoring

Observe for acute hypersensitivity after administration; ongoing monitoring relates to completion of the accompanying active vaccination course.

Counselling the patient

• This injection gives rapid but temporary protection and works best when given promptly after exposure.
• You will also need the hepatitis B vaccine course for lasting protection.
• Report any rash, breathlessness or other reaction after the injection.

Evidence & guidelines

HBIG use for post-exposure prophylaxis and in infants of infected mothers follows the UK immunisation guidance (Green Book).