Hepatitis B Vaccine Dosing
The recommended dose of hepatitis B vaccine varies by age, product, and clinical situation: for adults ≥20 years, standard dosing is either Engerix-B 20 μg (1.0 mL) or Recombivax HB 10 μg (1.0 mL) in a 3-dose series at 0,1, and 6 months, or alternatively Heplisav-B 20 μg (0.5 mL) in a 2-dose series at 0 and 1 month. 1
Standard Adult Dosing (Age ≥18-20 years)
Traditional 3-Dose Vaccines:
- Engerix-B: 20 μg (1.0 mL) per dose at 0,1, and 6 months 1, 2
- Recombivax HB: 10 μg (1.0 mL) per dose at 0,1, and 6 months 1
- PreHevbrio: 10 μg (1.0 mL) per dose at 0,1, and 6 months 1
Accelerated 2-Dose Vaccine:
- Heplisav-B: 20 μg (0.5 mL) per dose at 0 and 1 month (adults ≥18 years only) 1
- This achieves approximately 90% seroprotection compared to 70.5-90.2% with Engerix-B 1
Adolescent Dosing (Ages 11-19 years)
- Recombivax HB (ages 11-15): 10 μg (0.5 mL) in either a 2-dose schedule at 0 and 4-6 months OR a 3-dose schedule at 0,1, and 6 months 1
- Engerix-B (ages 11-19): 10 μg (0.5 mL) per dose in a 3-dose schedule at 0,1, and 6 months 1, 2
Pediatric Dosing (Ages 6 months to 10 years)
- Engerix-B: 10 μg per dose at 0,1, and 6 months 2
- This produces 98% seroprotection 1-2 months after the third dose with a GMT of 4,023 mIU/mL 2
Special Population Dosing
Hemodialysis and Immunocompromised Adults (≥20 years)
Critical dosing difference—standard doses are inadequate:
- Recombivax HB: 40 μg (1.0 mL) per dose in a 3-dose schedule at 0,1, and 6 months 1, 3
- Engerix-B: 40 μg (2.0 mL) per dose in a 4-dose schedule at 0,1,2, and 6 months 1, 2
- The 4-dose Engerix-B regimen achieves 67% seroprotection in hemodialysis patients 2
- Annual anti-HBs testing is required with booster doses when levels fall below 10 mIU/mL 3
Pregnant Women
- Only use: Engerix-B, Recombivax HB, or Twinrix 1, 3
- Do NOT use: Heplisav-B or PreHevbrio due to insufficient safety data in pregnancy 1, 3
Infants Born to HBsAg-Positive Mothers
- First dose within 12 hours of birth plus HBIG, then at 1-2 months and 6 months 3
- The final dose must not be administered before 24 weeks of age 3
Alternative Schedules
Accelerated Protection Schedule (Engerix-B)
- 0,1,2, and 12 months: Provides earlier seroprotection but requires a fourth dose at 12 months for long-term protection 1, 4
- After dose at month 2, GMT is only 53 IU/L, but a fourth dose at month 12 produces robust booster response 4
Twinrix (Combined Hepatitis A and B)
- Standard: 3 doses at 0,1, and 6 months (hepatitis B component is 20 μg per 1.0 mL) 1
- Accelerated: 4 doses at 0 days, 7 days, 21-30 days, and 12 months 1, 3
Critical Dosing Intervals
Minimum intervals that must be respected:
- Between doses 1 and 2: 4 weeks minimum 5, 3
- Between doses 2 and 3: 8 weeks minimum 5, 3
- Between doses 1 and 3: 16 weeks minimum 5, 3
- Doses given ≤4 days before the minimum interval are considered valid 5, 3
Interrupted Schedules
Never restart the series if interrupted—simply continue where you left off 5, 3
- If interrupted after dose 1, give dose 2 as soon as possible, then dose 3 at least 8 weeks after dose 2 5
- If only dose 3 is delayed, administer it as soon as possible 5
- Increasing intervals between doses has little effect on final immunogenicity and may actually increase antibody titers 3
Common Pitfalls to Avoid
- Do not use standard adult doses (10-20 μg) in hemodialysis patients—they require 40 μg doses 1, 3
- Do not give the third dose before 16 weeks from the first dose, even if 8 weeks have passed since the second dose 3
- Do not give the final infant dose before 24 weeks of age, as this may compromise long-term immunity 3
- Do not use Heplisav-B or PreHevbrio in pregnant women, children, or hemodialysis patients 1, 3
- Do not restart the series if interrupted—this wastes doses and delays protection 5, 3