Hepatitis B Immunoglobulin Vaccine
Overview
Hepatitis B Immunoglobulin (HBIG) is a preparation of human antibodies specific to the hepatitis B surface antigen that provides immediate passive protection against hepatitis B virus infection. Unlike the active hepatitis B vaccine which triggers the body to produce its own antibodies over weeks, HBIG delivers ready‑made antibodies that neutralize HBV and prevent the virus from infecting liver cells. It is used when rapid protection is needed after exposure to HBV, such as following needlestick injuries, mucosal exposure to infected blood, or sexual contact with a person known to carry hepatitis B. HBIG can also be administered to newborns born to hepatitis B surface antigen‑positive mothers to reduce the risk of perinatal transmission and, in some clinical settings, to prevent reinfection of the liver after transplantation in patients with chronic hepatitis B. Passive immunity from HBIG is temporary, lasting weeks to months, and is often used in conjunction with active hepatitis B vaccination when long‑term immunity is required.
Background and Date of Approval
Hepatitis B Immunoglobulin has been developed and licensed in many countries as a human plasma‑derived biological product for passive immunization against hepatitis B virus. Regulatory authorizations are based on evidence that HBIG effectively reduces the risk of HBV infection after defined exposures and in specific high‑risk groups when administered promptly. HBIG products are typically standardized by international units of anti‑HBs antibodies and are included in public health guidelines for post‑exposure prophylaxis and perinatal prevention. Its use has been incorporated into global and national strategies for hepatitis B prevention alongside active vaccination programmes to minimize chronic HBV infection and its complications.
Uses
Hepatitis B Immunoglobulin is indicated for post‑exposure prophylaxis in individuals exposed to hepatitis B virus through needlestick injuries, mucosal contact with infected blood, or sexual exposure within defined timeframes. It is recommended for newborn infants born to mothers positive for hepatitis B surface antigen to reduce vertical transmission when administered soon after birth. HBIG may also be used in persons with incomplete or unknown hepatitis B vaccination status who face high‑risk exposures, and in combination with active hepatitis B vaccination to ensure immediate and long‑term protection. In selected clinical contexts, such as liver transplantation for HBV‑related liver disease, HBIG is employed to prevent reinfection of the graft.
Administration
Hepatitis B Immunoglobulin is administered by intramuscular injection. For post‑exposure prophylaxis in adults and children, a standard dose is approximately 0.06 mL per kilogram of body weight given as soon as possible after exposure, ideally within 24 hours. For newborn infants born to hepatitis B surface antigen‑positive mothers, a typical dose is 0.5 mL intramuscularly administered within 12 hours of birth. When indicated, a second dose may be given a month after exposure in selected scenarios, such as non‑responders to hepatitis B vaccine or those who decline vaccination. HBIG is given at a separate anatomical site from the hepatitis B vaccine when both are administered.
Side Effects
Common side effects of Hepatitis B Immunoglobulin include pain, redness, swelling, or tenderness at the injection site, mild fever, headache, fatigue, and dizziness. Some individuals may report nausea or general malaise following administration. Most of these reactions are mild and transient, resolving within a few days without long‑term consequences.
Warnings
Serious adverse events are uncommon but may include severe allergic reactions such as anaphylaxis, particularly in individuals with a history of hypersensitivity to immunoglobulin products or IgA deficiency. Severe local reactions and, rarely, systemic responses may occur. HBIG should be used with caution in patients with coagulation disorders that contraindicate intramuscular injections and in those with a history of severe allergic reactions to human plasma‑derived products. Vaccination with live attenuated vaccines should be delayed for several months after HBIG administration due to potential interference with vaccine efficacy.
Precautions
Before administering Hepatitis B Immunoglobulin, healthcare providers should assess for a history of severe allergic reactions to human immunoglobulin or other blood products. Live vaccines administered within three months before or after HBIG may have reduced effectiveness, and appropriate scheduling is recommended. HBIG may alter serologic test results for antibody measurements, and clinicians should consider this when interpreting tests. Careful clinical monitoring following administration can help identify rare serious reactions and guide further management.
Expert Tips
Ensure prompt administration of Hepatitis B Immunoglobulin after exposure to maximize prophylactic benefit, ideally within 24 hours of exposure. Confirm appropriate dosing based on weight and clinical scenario, and administer HBIG at a different site from any concomitant hepatitis B vaccine. Educate patients and caregivers on the temporary nature of passive immunity and the importance of completing the hepatitis B vaccination series for long‑term protection. Monitor for injection site reactions and any signs of hypersensitivity. Coordination with public health and immunization programmes enhances the integration of HBIG into comprehensive hepatitis B prevention strategies.