Thune says ‘very concerned’ about Trump admin Tylenol autism warning

WASHINGTON — Senate Republican Leader John Thune said he is very concerned about the Trump administration’s warning linking acetaminophen use during pregnancy to autism, urging that science should guide health guidance and policy. In an appearance on CNN's Inside Politics on Wednesday, Thune said there are studies referenced by the administration, but many in the medical community would reach different conclusions about Tylenol's safety in pregnancy.

Administration officials on Monday announced that acetaminophen, the active ingredient in Tylenol, may be associated with a very increased risk of autism in children when used late in pregnancy. They cited a collection of studies that they said show associations, though not a proven cause-and-effect relationship. President Trump repeatedly advised pregnant women on Monday to avoid Tylenol, prompting questions about the messaging.

Thune said the public requires oversight and a well-documented process to ensure policy is grounded in science. He urged that decisions be guarded, with science and medical advice from experts guiding the process and that the actions be well documented. He noted that while the administration cited studies, many in the medical community would reach different conclusions about acetaminophen use.

On Tuesday, Sen. Bill Cassidy, a physician who chairs the Senate committee that oversees health care policy, said the preponderance of evidence shows there is no solid link between acetaminophen and autism diagnoses. Cassidy called on Kennedy to release the data used by the administration to support the claim, writing on X that the concern is that women will be left with no options to manage pain in pregnancy and that lawmakers must be compassionate to this problem.

The American College of Obstetricians and Gynecologists and Kenvue, the Tylenol maker, were swift in their responses. ACOG said decisions must be grounded in science and stressed the importance of trust in the decision-making process, while Kenvue said it strongly disagrees with the claim and noted that the studies cited by the White House do not establish causation.

The debate highlights the political sensitivity around communicating uncertain scientific findings to pregnant women, and the stakes of pain management during pregnancy. Acetaminophen is widely used by pregnant people and remains a common recommendation when clinically appropriate. The White House framed the issue as a public health caution, while critics argued that broad warnings could have unintended consequences, including anxiety and reduced access to safe medications.

Looking ahead, lawmakers are likely to press Kennedy to release underlying data and to demand more transparent review of the science. The issue underscores broader tensions over how science informs policy, particularly as political dynamics intersect with health guidance and electoral considerations.