Giving babies Tylenol to prevent fever when they get childhood vaccinations may backfire and make the shots a little less effective, surprising new research suggests.
It is the first major study to tie reduced immunity to fever-lowering medicines. Although the effect was small and the vast majority of kids got enough protection from vaccines, the results make a compelling case against routinely giving Tylenol after vaccination, say doctors from the Centers for Disease Control and Prevention. They wrote an editorial accompanying the study, published in today’s issue of the British medical journal Lancet.
The study only looked at preventive use of Tylenol — not whether it is OK to use after a fever develops.
Tylenol, or generic acetaminophen, is widely recommended as a painkiller for babies. Many parents give it before or after a shot to prevent fever and fussiness. The CDC’s vaccine advisory panel says it is a reasonable thing to do for children at high risk of seizures, which can be triggered by fevers.
But curbing fever, especially the first time a baby gets a vaccine, also seems to curb the immune response and the amount of protective antibodies that are made, the new study found.
