U.S. Appeals Court Revives Over 500 Tylenol Autism Lawsuits

The 2nd U.S. Circuit Court of Appeals in Manhattan issued a ruling on July 13, 2026 that revived more than 500 private lawsuits against Kenvue, the maker of Tylenol. The plaintiffs allege that prenatal exposure to acetaminophen, the active ingredient in Tylenol, caused autism spectrum disorder and attention‑deficit/hyperactivity disorder in their children. The court found that the district court had improperly excluded expert testimony offered by the families, allowing that evidence to be reconsidered.

The litigation is part of a multidistrict proceeding in the Southern District of New York that began in 2022. While no scientific consensus links acetaminophen to autism or ADHD, the U.S. Food and Drug Administration has warned that use during pregnancy may be associated with increased risk of neurological conditions, and medical societies consider the drug safe when used as directed. Kenvue, which was spun off from Johnson & Johnson in 2023, recently agreed to be acquired by Kimberly‑Clark for more than $40 billion; its shares fell 10 cents to $19.38 following the decision.