Comvax Disease Interactions

Hepatitis B vaccine (adult and pediatric) is usually for intramuscular administration. However, it may be administered subcutaneously to persons at risk for hemorrhage following intramuscular injections (e.g., hemophiliacs), although it may result in lower antibody response. Additionally, when other aluminum- absorbed vaccines have been administered subcutaneously, an increased incidence of local reactions including subcutaneous nodules has been observed. Therefore, consider subcutaneous administration only in persons who are at risk of hemorrhage following intramuscular injections.

Hepatitis B vaccine should be deferred for infants with a birth weight less than 2,000 grams if the mother is documented to be HBsAg negative at the time of the infant's birth. If the mother is HBsAg positive (or the status cannot be determined), the infant should receive the vaccine within 12 hours after birth.
Apnea following intramuscular vaccination has been observed in some infants born prematurely and the decision to administer any intramuscular vaccine, including hepatitis B vaccine, should be based on consideration of the infant's medical status, and the potential benefits and risks of vaccination. Close monitoring is recommended.