Call for court overseeing lawsuits on Tylenol-autism link to consider Trump administration’s stance 

Families appealing against the dismissal of their lawsuits alleging that Kenvue’s Tylenol, or generic versions of the pain-relief medication, caused their children’s autism are asking an appeals court to consider US President Donald Trump’s new advice that pregnant women avoid the painkiller as it decides whether to revive their lawsuits.

Ms Ashley Keller, an attorney representing the plaintiffs, filed a letter on Sept 25 alerting the New York-based 2nd US Circuit Court of Appeals to the Trump administration’s stance on the alleged link between Tylenol and autism.

In a news conference at the White House on Sept 22, Mr Trump delivered medical advice to pregnant women, repeatedly telling them not to use acetaminophen – also known as paracetamol – the active ingredient in Tylenol.

A judge in 2024 dismissed hundreds of lawsuits alleging a connection between Tylenol or generic versions of the drug and autism or attention deficit hyperactivity disorder diagnoses, saying the experts whom the plaintiffs relied on had failed to support their conclusions with scientific evidence.

In the letter on Sept 24, Ms Keller told the appeals court that a ruling upholding the lower court’s decision would pose “grave separation of powers concerns” because the Trump administration had turned to the same experts in developing its position.

Ms Keller noted that during the press conference on Sept 22, US Food and Drug Commissioner Marty Makary, Health Secretary Robert F. Kennedy Jr, and Mr Trump cited the

research on Tylenol and autism done by Dr Andrea Baccarelli,

currently dean of the faculty at the Harvard T.H. Chan School of Public Health, one of the plaintiffs’ experts.

In a statement, a Kenvue spokesperson noted that the Food and Drug Administration said a causal relationship has not been established between Tylenol and autism and said the company believes it will continue to be successful in the litigation as the claims lack legal merit and scientific support.

More than 500 lawsuits dismissed

US district Judge Denise Cote in Manhattan in 2024 dismissed more than 500 lawsuits against Kenvue and retailers that sold store-brand acetaminophen.

Judge Cote had ruled in 2023 that none of the expert witnesses offered by the plaintiffs to testify at trial that acetaminophen could cause the conditions had used a sound scientific methodology. She said the experts’ “unstructured approach” allowed “cherry-picking” and a “results-driven analysis”.

Product liability lawsuits, like the ones over acetaminophen, rely on experts to establish that a product is capable of causing the alleged harm.

The 2nd Circuit is slated to hear arguments on Oct 6 in the plaintiffs’ appeal of the judge’s decision.

In the letter on Sept 24, Ms Keller argued that a decision “holding that a jury may not hear the same expert evidence that the executive branch credited will badly damage the public trust required for the executive to take care that the public-health laws are faithfully executed”.

Legal experts have said it would be unusual if the appeals court gave the administration’s actions and Mr Trump’s comments much weight in considering how to move forward with the cases.

“It’s not as if there’s been a new study that has been announced that has a different conclusion,” Professor Elizabeth Chamblee Burch, at the University of Georgia’s School of Law whose research focuses on cases like the Tylenol litigation, said on Sept 23 before Ms Keller filed the letter.

Researchers say there is no firm evidence of a link between the use of Tylenol and autism. A 2024 study of nearly 2.5 million children in Sweden found no causal link between in utero exposure to paracetamol and neurodevelopmental disorders.

A 2025 review of 46 studies that Dr Baccarelli participated in did suggest a link between prenatal paracetamol exposure and increased risks of these conditions. But the researchers from the Icahn School of Medicine at Mount Sinai, Harvard University and others said the study does not prove the drug caused the outcomes. REUTERS