Home / Ask The Experts / The adult formulation of Engerix-B contains twice as much antigen per dose as the adult formulations of Recombivax HB. If a patient received 10 mcg (1 mL) of Recombivax for the first dose, and I stock only Engerix-B, should I give a 10 mcg (0.5 mL) dose of Engerix-B for subsequent doses?

Hepatitis B
Vaccine Recommendations

The adult formulation of Engerix-B contains twice as much antigen per dose as the adult formulations of Recombivax HB. If a patient received 10 mcg (1 mL) of Recombivax for the first dose, and I stock only Engerix-B, should I give a 10 mcg (0.5 mL) dose of Engerix-B for subsequent doses?

No. It is the volume of the dose, not the antigen content, that is important. People 20 years and older should always receive a 1.0 mL dose of either Engerix-B or Recombivax HB when using those products. Likewise, people younger than 20 years should always receive a 0.5 mL dose of the pediatric formulation of either Engerix-B or Recombivax HB.

Last reviewed: July 21, 2023

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This page was updated on July 21, 2023.