What Does the Science Say About Tylenol and Autism?

Is Tylenol linked to increased risk of autism?
Short answer: There isn’t much evidence to back this up.
Long answer: …
We’ll try to cover as much as we can.
Let’s start with this 2024 study from Sweden, which looked at nearly 2.5 million children…
The study found that acetaminophen use during pregnancy was associated with “marginally increased risk of autism.”
But, in models where siblings were analyzed, the researchers “found no evidence that acetaminophen use during pregnancy was associated with autism.”
Another study from Japan—which looked at more than 200,000 children—found no link at all.
So, why do some people think there’s a link?
Recently, a review of research published by Harvard analyzed the results of 46 previous studies, the majority of which supported evidence of a link. The FDA notes the link is “most pronounced when acetaminophen is taken chronically throughout pregnancy.”
However, both the FDA and the Harvard researchers note that acetaminophen is taken to treat pain and high fevers during pregnancies.
Neither group recommends a broad limitation on acetaminophen use.
Today, according to the CDC, 1 in 31 kids are diagnosed with autism spectrum disorder — and if that number seems high, experts say it’s because of a broadened definition, better screenings, and more research showing that ASD is likely genetic.
Also, acetaminophen became widely available under the Tylenol brand more than a decade after autism was first diagnosed.
That feels important to note too.