Vaccination Schedule for Twinrix

Approved Dosage Schedules

The Centers for Disease Control and Prevention recommends a standard schedule of 3 doses (0, 1, and 6 months) or an accelerated schedule of 4 doses (0, 7 days, 21-30 days, and 12 months) for adults ≥18 years 1, 2, 3
The American Academy of Pediatrics recommends a dose of 1 mL by intramuscular injection containing 720 EL.U of hepatitis A antigen and 20 μg of hepatitis B antigen 4
The standard schedule is the most commonly used and suits the majority of adult patients, with doses administered at 0, 1, and 6 months 1, 2, 4

If the vaccination schedule is interrupted, do not restart the series; simply administer the next dose as soon as possible, with at least 8 weeks between the second and third doses 1, 2, 5
For the accelerated schedule, the third dose can be administered between 21 and 30 days after the first dose, and the fourth dose is essential for long-term protection, to be given 12 months after the first dose 1, 2, 3, 5

The Twinrix vaccine can be used in pregnant women requiring vaccination against hepatitis A and B, as it is one of the recommended vaccines for this population 6
Immunodeficient conditions are not a contraindication to Twinrix, as the vaccine is inactivated and has not shown increased safety risks in immunodeficient individuals 4

The vaccine should be administered via the intramuscular route only, with the needle length adapted to the patient's age and size, and the vaccine should be shaken well before administration to obtain a slightly opaque white suspension 4

Do not restart the series if the schedule is interrupted; continue where you left off, and do not forget the fourth dose at 12 months in the accelerated schedule, as it is crucial for long-term protection 1, 2, 5, 6

The CDC MMWR recommends administering Twinrix at months 0, 1, and 6, which provides protective immunity well before a traveler’s departure that is 2–3 months away【7】.
After the first two doses (months 0 and 1), most adult travelers achieve substantial hepatitis A and B immunity, allowing travel without waiting for the third dose【7】.

Each 1 mL Twinrix dose contains 720 EL.U. of hepatitis A antigen and 20 µg of hepatitis B surface antigen, delivering combined protection against both viruses【7】.

Twinrix should be given intramuscularly into the deltoid muscle, using a needle length appropriate for the patient’s size【7】.
The vaccine is approved for use in adults aged 18 years and older【7】.

Store Twinrix at 2 °C–8 °C (35.6 °F–46.4 °F) and protect it from freezing to maintain potency【7】.