The scientific community is expressing confusion and overwhelming criticism following President Donald Trump and his administration's claim on Monday that acetaminophen — the active ingredient in Tylenol — is linked to autism.
The Food and Drug Administration said it is advising doctors to limit its use during pregnancy, despite countless medical organizations maintaining that the medication is safe for pregnant women.
Many of those same medical organizations have warned that potential risks of not addressing fevers with acetaminophen properly may lead to heart and facial defects in babies, as well as preterm labor.
The White House and FDA are focusing on one newer study from Mount Sinai that suggests prenatal exposure to acetaminophen may increase the risk of neurodevelopmental disorders, including autism and ADHD. However, the study itself notes that further research is needed to confirm the associations and determine causality.
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Dr. Brian Lee, a biostatistician and epidemiologist with Drexel University who has studied potential prenatal factors in neurodivergent diagnoses, emphasized the importance of genetics in autism research.
"The big elephant in the room for neurodevelopmental disorders is genetics. Autism is a highly heritable condition, and genetics, when you just look at users versus non-users, it sort of ignores that aspect," Lee said.
"I think what people should take away from all of this is that physicians remain the sort of the keystone in terms of being the best source of information, because they are the ones who have to process the scientific information," Lee added.
Kenvue, the maker of Tylenol, has also pushed back against the White House in a statement, writing that "over a decade of rigorous research endorsed by leading medical professionals and global health regulators confirms there's no credible evidence linking acetaminophen to autism."
The World Health Organization, American Academy of Pediatrics, and American College of Obstetricians and Gynecologists are holding firm in their research and data from the past couple of decades.
The administration bypassed typical FDA approval processes in changing language on Tylenol bottles and advising that another supplement, leucovorin, is an option for treating autism — despite it not going through the FDA approval process either.
"The difficulty with promoting leucovorin at this time is that the existing evidence for leucovorin and for treatment or alleviation of autism symptoms is remarkably premature," said Lee. "There's only been a handful of very small studies which have some methodological issues, but no therapeutic recommendations, in my opinion, should be made based on this really preliminary evidence. In short, more research is needed."
In referring to the recent study cited by the Trump administration, medical experts point out the key difference between association and causation.
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"This is where it gets tricky. Association means that if people take Tylenol in pregnancy, they may have a child who has autism," explained Dr. Kristin Lyerly, who is a practicing OB-GYN. "But association does not mean that something causes something. Ice cream is associated with drowning. It doesn’t cause you to drown. They’re just two things that are present when the weather is warm."
Pregnancy research is often limited to observational studies, making it difficult to account for genetic and environmental factors — something particularly important in autism research.
Doctors emphasize that for pregnant women with fevers or debilitating pain, Tylenol is currently one of the only guided medications considered safe. Not treating these conditions could be more harmful for both the pregnant woman and child.
Medical professionals also express concern about placing blame on mothers, suggesting that if they took Tylenol and their child received an autism diagnosis, it's their fault. This adds to stigma around the diagnosis when there's no firm medical research backing up the claims.
Meanwhile, the European Union has said it's not changing its guidance at all regarding acetaminophen use during pregnancy.
This story was reported on-air by a journalist and has been converted to this platform with the assistance of AI. Our editorial team verifies all reporting on all platforms for fairness and accuracy.
