Usual Adult Dose for Exposure to Hepatitis B Virus

Prevention of recurrence following liver transplantation:
HBIG 20,000 international units IV once with the grafting of the transplanted liver (the anhepatic phase)
Week 1 postoperative: 20,000 international units IV daily from day 1 to 7
Week 2 to 12 postoperative: 20,000 international units IV every two weeks from day 14
Month 4 onwards: 20,000 international units IV monthly

If patients fail to reach anti-HBs levels of 500 international units/L within the first week post-liver transplantation, dosage adjustments may be required.

Dosage regimen should be increased to 10,000 international units IV every 6 hours until the target anti-HBs are reached in patients who are especially susceptible to extensive loss of circulated anti-HBs, such as those who have surgical bleeding or abdominal fluid drainage (greater than 500 mL) or patients who undergo plasmapheresis.

Percutaneous or permucosal blood exposure:
Source is HBsAg-positive and exposed person has been vaccinated:
If exposed person's anti-HBs level is less than 10 sample ratio units (10 million international units) by RIA or negative by EIA:
Hepatitis B immune globulin (HBIG) 0.06 mL/kg IM once plus
hepatitis B vaccine booster dose or second dose of hepatitis B immune globulin 1 month later.

Source is HBsAg-positive and exposed person is unvaccinated:
HBIG 0.06 mL/kg IM once plus start hepatitis B vaccine series.

Source is high risk for HBsAg-positive and exposed person has been vaccinated:
Previously vaccinated exposed person:
If vaccine nonresponder and source is HBsAg-positive, give HBIG 0.06 mL/kg IM once plus hepatitis B vaccine booster dose or second dose of hepatitis B immune globulin 1 month later.
If exposed person does not respond to at least 4 doses of vaccine, give 2 doses of HBIG.

Source is high risk for HBsAg-positive and exposed person is unvaccinated:
Start hepatitis B vaccine series within 7 days of exposure
plus HBIG 0.06 mL/kg IM once if source tests positive for HBsAg.

Source unknown or low risk for HBsAg-positive and exposed person is vaccinated:
No treatment required.

Source unknown or low risk for HBsAg-positive and exposed person is unvaccinated:
Start hepatitis B vaccine series within 7 days of exposure.

Sexual exposure to HBsAg-positive source:
HBIG 0.06 mL/kg IM once
plus start hepatitis B vaccine series within 14 days of last contact or if contact will continue.

Usual Pediatric Dose for Exposure to Hepatitis B Virus

Nabi-HB(R), prophylaxis of infants born to HBsAg positive mothers:

• Mother is known positive for HBsAg: 0.5 mL intramuscularly at birth (within 12 hours); repeat dose at 1 and 6 months.
• Mother not screened for HBsAg: If mother found positive after screening, 0.5 mL intramuscularly as soon as possible, no later than 1 week after birth; repeat dose at 1 to 2 months and again at 6 months.
• Infants should receive their first hepatitis B vaccination within 12 hours of birth.

• Confirmed HBsAg-positive:
• Unvaccinated: 0.06 mL/kg intramuscularly immediately; administer concurrently with hepatitis B vaccine.
• Vaccinated: If test for anti-HBs is inadequate, 0.06 mL/kg intramuscularly immediately; administer concurrently with hepatitis B vaccine booster or a second immune globulin dose one month later.

• Known source, high risk for HBsAg-positive:
• Unvaccinated: Initiate hepatitis B vaccine series; if test for anti-HBs is inadequate, 0.06 mL/kg intramuscularly.
• Vaccinated: Test source for HBsAg only if exposed is vaccine non-responder; if source is HBsAg positive, give 0.06 mL/kg intramuscularly immediately; administer concurrently with hepatitis B vaccine booster or a second immune globulin dose one month later.

• Known source, low risk for HBsAg-positive:
• Unvaccinated: Initiate hepatitis B vaccine series
• Vaccinated: No action required

• Unknown source:
• Unvaccinated: Initiate hepatitis B vaccine series
• Vaccinated: No action required

• If hepatitis B vaccine is refused or in known vaccine non-responders, administer a second dose one month after the first dose.

• Infants under 12 months old: 0.5 mL intramuscularly; administer concurrently with hepatitis B vaccine.
• Treatment of other household members is not recommended without an identifiable blood exposure (e.g. shared toothbrushes or razors), then treat like sexual exposures.

Renal Dose Adjustments

Data not available

Liver Dose Adjustments

Data not available

Dose Adjustments

Prevention of hepatitis B recurrence following liver transplantation:

• Dose adjustments may be required if patient fails to reach anti-HB levels of 500 international units per liter within the first week post-liver transplantation.
• Patients with surgical bleeding or abdominal fluid drainage over 500 mL, or who undergo plasmapheresis are particularly susceptible to extensive loss of circulated anti-HBs.
• In these cases, increase dosing regimen by a half dose (10,000 international units) intravenously every 6 hours until target anti-HBs is reached.

Precautions

CONTRAINDICATIONS:

• Anaphylactic or severe systemic reactions to parenteral human globulin preparations
• IgA deficient may develop anti-IgA antibodies which may lead to an anaphylactoid reaction; this drug contains less than 40 micrograms IgA per milliliter.
• HepaGam B(R) must be given intramuscularly for postexposure prophylaxis; patients with severe thrombocytopenia or coagulation disorders that contraindicate intramuscular injections should only be given this drug if benefits outweigh risks.

Dialysis

Data not available

Other Comments

Hepatitis B immune globulin should stored under refrigeration. Do not freeze and do not use solution that has been frozen. Use within 6 hours of entering the vial; discard partially used vials.

Administer HBIG as soon as possible after exposure, preferably within 24 hours. Its efficacy is unknown when given beyond 7 days.

If hepatitis B vaccine is given concomitantly, it should be administered into a different site.

HBIG should be administered through a separate intravenous line using an intravenous administration set via infusion pump.

The rate of administration should be set at 2 mL per minute. It should be decreased to 1 mL per minute or slower if the patient develops discomfort, infusion-related adverse events or there is concern about the speed of infusion.

Regular monitoring of serum HBsAg and levels of anti-HBs antibody should be performed pre-infusion to track treatment responses and allow for treatment adjustment.