The manufacturer of Tylenol and several major U.S. retailers petitioned a federal appeals court on Thursday, September 10, 2026, to reconsider a decision that allowed more than 500 lawsuits to proceed. The legal actions involve allegations that the use of acetaminophen, the active ingredient in Tylenol, during pregnancy is linked to autism and attention deficit hyperactivity disorder (ADHD) in children.
The request follows a July 13 ruling by the 2nd U.S. Circuit Court of Appeals in Manhattan that revived the private lawsuits. Those cases had previously been dismissed by a district judge who determined that the scientific testimony provided by the plaintiffs was not reliable enough for a trial.
In the Thursday filing, Kenvue—the maker of Tylenol—and retailers including Walmart, CVS, and Walgreens argued that the appeals court failed to respect the role of district judges as "gatekeepers" of evidence. The companies stated that lay juries lack the specialized knowledge required to resolve complex scientific questions and argued that the plaintiffs' theories should not be presented at trial.
U.S. District Judge Denise Cote had originally excluded testimony from three experts: Andrea Baccarelli of Harvard, Eric Hollander of the Albert Einstein College of Medicine, and Brandon Pearson, formerly of Columbia University. The defendants have asked the appeals court to either reverse its revival of the suits or instruct Judge Cote to re-evaluate whether the experts' opinions are admissible.
While Donald Trump and top U.S. health officials suggested a possible link to autism in September 2025, medical societies generally consider acetaminophen the preferred treatment for pain and fever during pregnancy. There is no firm scientific evidence of a link. Kenvue, based in New Jersey, was spun off from Johnson & Johnson in 2023.
The litigation involves hundreds of families who have filed suit seeking damages for developmental disorders they attribute to prenatal acetaminophen exposure. With more than 500 private lawsuits currently revived, the outcome of this appeal will determine whether these parents and guardians can present their claims to a jury or if the cases will be dismissed for a second time. The named retailers include national chains like Target, Costco, Kroger, Dollar General, and 7-Eleven.
Acetaminophen is currently recommended by many doctors as the standard treatment for fever and pain during pregnancy. The defendants argue that allowing "unsettled scientific questions" to reach a jury undermines the established role of judges in vetting evidence. The 2nd U.S. Circuit Court of Appeals rarely reconsiders its own decisions. No specific date for a new ruling has been reported.