Why is Pediarix not recommended for booster doses?
Pediarix is not FDA approved for doses four or five of the DTaP series. This makes sense because using Pediarix for the 4th and 5th doses would result in a lot of extra doses of Hepatitis B. If the child received a birth dose of Hepatitis B vaccine and then 4 or 5 doses of Pediarix, that would mean the child received 5 or 6 doses of Hepatitis B vaccine, which is far more than is recommended and far more than anyone needs.