Babies are often given acetaminophen when they get their routine vaccinations. The drug, sold as Tylenol in the United States and called paracetamol in most countries, counters the common risk of fever and the much less common risk of fevers high enough to cause seizure.
But a new study, done in the Czech Republic and published last week in The Lancet, may have implications for children everywhere: the researchers found that the antifever drug makes some vaccines less potent. Fever is part of the immune response, and suppressing it, the authors said, appeared to impair the body’s ability to make antibodies.
I certainly understand the need for the body to have a powerful immune response for a vaccine to be effective.
While it's outside the scope of the study, you might want to hold off popping down a couple Tylenol when you get your flu shot(s).