Hepatitis B Vaccine (rDNA) is a sterile suspension containing the Hepatitis B surface antigen (HBsAg) produced by recombinant DNA technology in yeast cells (*Saccharomyces cerevisiae*). The 20 mcg dose is the standard adult formulation used for active immunization against infection caused by all known subtypes of the Hepatitis B virus. It induces the production of specific anti-HBs antibodies, providing protection against acute and chronic hepatitis B, cirrhosis, and hepatocellular carcinoma.
Adult: 20 mcg (1.0 mL) intramuscularly, as a 3-dose schedule at 0, 1, and 6 months. An alternative 0, 1, 2, and 12-month schedule can be used for rapid induction.
Note: Shake vial/syringe well before use. Administer by intramuscular injection into the deltoid muscle in adults and older children. The anterolateral thigh is preferred for infants. Do NOT inject intravenously, intradermally, or subcutaneously (can reduce immunogenicity). Use a separate, sterile syringe and needle for each individual.
The vaccine contains the Hepatitis B surface antigen (HBsAg) adsorbed onto aluminum hydroxide adjuvant. Upon intramuscular injection, the antigen is taken up by antigen-presenting cells (APCs) at the site and in draining lymph nodes. APCs process and present HBsAg peptides on Major Histocompatibility Complex (MHC) class II molecules to CD4+ T-helper cells. Activated T-helper cells stimulate antigen-specific B-lymphocytes to proliferate and differentiate into plasma cells, which secrete protective anti-HBs antibodies (IgG). Memory B-cells and T-cells are also generated, providing long-term immunity.
Pregnancy: Pregnancy Category B. No evidence of risk to fetus. Hepatitis B infection poses a severe risk to mother and neonate. Vaccination is recommended for susceptible pregnant women at risk of infection. It is a key component of preventing maternal-to-child transmission.
Driving: No effect. However, syncope can occur shortly after vaccination; patients should be observed for 15 minutes.
| Immunosuppressants (e.g., high-dose corticosteroids, chemotherapy, biologics) | Diminished immunogenic response; may not achieve protective antibody titers. | Major |
| Other Vaccines (e.g., DPT, OPV, IPV, Hepatitis A) | Can be administered simultaneously at different sites without interference. Immune response may be slightly reduced for some co-administered antigens but remains protective. | Moderate |
| Hepatitis B Immunoglobulin (HBIG) | Can be administered simultaneously at a different site for post-exposure prophylaxis without affecting active immunity. | None |
Same composition (Hepatitis B Vaccine (rDNA) (20mcg)), different brands: