Key facts
- A federal appeals court revived over 500 lawsuits against Tylenol maker Kenvue.
- The court ruled that a district court judge improperly excluded expert testimony.
- The excluded testimony linked Tylenol use during pregnancy to autism and ADHD in children.
- Kenvue maintains that credible science shows no proven link between acetaminophen and autism or ADHD.
- The lawsuits will return to the district court for further proceedings.
A federal appeals court has revived more than 500 private lawsuits against Kenvue, the maker of Tylenol, concerning the painkiller's alleged link to autism and ADHD. The 2nd U.S. Circuit Court of Appeals in Manhattan ruled that a district court judge had improperly excluded expert testimony from three doctors. These experts, including the dean of Harvard University's School of Public Health, had provided testimony linking the use of Tylenol during pregnancy to developmental disorders in children.
Circuit Judge Guido Calabresi, writing for a three-judge panel, stated that the excluded testimony reflected methodologies used by other scientists and constituted acceptable interpretations of scientific evidence, even where disagreement exists among scientists. The court emphasized that this decision does not determine whether acetaminophen causes autism or ADHD, nor does it address whether officials should take further action to protect public health.
Kenvue, however, maintains that Tylenol is safe and that credible, independent science shows no proven link between acetaminophen use and autism or ADHD. The company plans to challenge the plaintiffs' experts' opinions again in court. Many retailers, including CVS, Kroger, Target, Walgreens, and Walmart, were also named as defendants in the original lawsuits.
The lawsuits were initially dismissed in December 2024 by U.S. District Judge Denise Cote, who had criticized the methodology of the plaintiffs' expert witnesses. Monday's decision by the appeals court sends the cases back to Judge Cote for further proceedings. Kenvue was spun off from Johnson & Johnson in 2023 and is currently being acquired by Kimberly-Clark.