Second Circuit Reinstates Tylenol MDL

Ben Cannon

Author

Trump Administration Got It Right about Pregnant Women and Autism

On July 13, 2026, the United States Court of Appeals for the Second Circuit reversed the dismissal of the multidistrict litigation alleging that prenatal acetaminophen exposure causes autism spectrum disorder and ADHD in children. The ruling reinstates the MDL and returns it to the Southern District of New York for further proceedings.

While it is possible that the lower court will dismiss the case again, this new ruling gives mothers and families of children affected by prenatal Tylenol exposure a renewed opportunity to obtain justice for their injuries.

This decision follows the Trump Administration’s correct order in September 2025. The Administration required that women be warned: excessive use of Tylenol during pregnancy increases the risk of a baby being born with autism.

For the clients of Watts Law Firm LLP, this is a major victory. Our clients and others affected  have long understood the link between Tylenol and autism. They have lived with the resulting effects and the real-life consequences. Now, mothers and families have a renewed opportunity to obtain justice for their injuries.

How the Tylenol Cases Got Shut Down

For years, these families fought. Watts Law Firm LLP, alongside co-counsel, stood with them.

In December 2023, Judge Denise Cote excluded every single one of the plaintiffs’ general causation experts. Their testimonies were out. Two weeks later, in January 2024, she followed up with a subsequent order under Federal Rule of Evidence 702. She dismissed all active federal cases. The plaintiffs had no admissible evidence left. The MDL, which held roughly 550 cases, was dismissed.

The setback was severe. However, we appealed and Watts Law Firm LLP immediately began exploring new scientific evidence that could reinvigorate the case. The team considered refiling cases for minors in state courts. They prepared for potential state court litigations. They pursued appellate avenues. Every option was on the table.

The litigation stems from a simple, devastating concern. Acetaminophen, widely recommended as a safe pain relief option for pregnant women, may not be safe at all. Scientific inquiries have suggested a possible link between APAP exposure during pregnancy and increased risks of neurodevelopmental disorders in children, such as Autism Spectrum Disorder (ASD). Despite acetaminophen’s reputation, recent studies and expert opinions have called that assumption into question. They advocate for more cautious use. The companies knew. The mothers did not.

The defendants are Johnson & Johnson and its successor entities selling Tylenol, including Kenvue, Inc. and Kimberly Clark Corporation. These companies knew their products were causing harm. They refused to warn pregnant women because they did not want to lessen sales. They kept the risk quiet. They kept the money flowing.

The Trump Administration Takes Action: Women Must be Warned About the Risk

According to an HHS announcement from September 22, 2025, the Trump Administration began the process to initiate a safety label change for acetaminophen. The agency issued a physician notice and launched a nationwide public service campaign to inform families and protect public health.

The Trump Administration, through the FDA, recognized that prior clinical and laboratory studies suggest a potential association between acetaminophen use during pregnancy and adverse neurodevelopmental outcomes. It encouraged clinicians to use the lowest effective dose for the shortest duration when treatment is required. It partnered with manufacturers to update labeling and drive new research.

That government action matters. The Trump Administration did not wait for the courts to finish arguing. It followed the science and warned the public. Now the litigation can proceed with the full weight of that official recognition behind it.

The science continues to develop. The National Institutes of Health is currently funding the Autism Data Science Initiative, which supports 13 projects totaling more than $50 million. These projects examine environmental, nutritional, medical, and social factors alongside genetics using advanced methods such as machine learning. New research may strengthen the connection between prenatal acetaminophen exposure and neurodevelopmental disorders.

The Second Circuit did not hand the plaintiffs a victory at trial. It handed them another chance. The court explicitly stated that it does not prejudge whether the admissible expert testimony, viewed alongside the totality of the evidence and the defendants’ experts, will suffice to raise a genuine issue of fact. That question remains for the lower court to decide.

Still, hundreds of thousands of mothers took Tylenol during pregnancy. Their children were born with autism. The companies failed to warn them. The government has now acknowledged the potential risk. The courts have reopened the cases. And the families will have their opportunity to seek justice.

What the Second Circuit Held

While the federal government took action, the families still need the courts. On July 13, 2026, the United States Court of Appeals for the Second Circuit agreed that the lower court got it wrong.

In a victory for that work of Trump scientists, the Second Circuit ruled past Tylenol autism cases should proceed to trial because three highly respected and “concededly qualified experts offered opinions that comport with methodologies applied by other scientists in their fields, and constitute acceptable interpretations of scientific evidence.” Opinion, p. 7.

The Second Circuit then reversed Judge Cote’s dismissal and reinstated the MDL. The appeals court found that Judge Cote had exceeded her discretion by excluding three of the plaintiffs’ general causation experts. These experts, the court held, used methodologies that other scientists in their fields apply. Their interpretations of the scientific evidence were acceptable.

One of those experts is Dr. Andrea Baccarelli, Dean of the Harvard T.H. Chan School of Public Health. The court ruled that his testimony, and that of two other qualified experts, should be heard.

The Second Circuit did not give the plaintiffs a free pass. The court upheld Judge Cote’s exclusion of two other experts. It also ordered her to re-analyze an alternative expert that the plaintiffs had proposed. And the court rejected the defendants’ preemption argument. Federal law does not bar these failure-to-warn claims.

Importantly, the Second Circuit did not decide that the plaintiffs will win. The court stated explicitly that it does not prejudge whether the admissible expert testimony, taken together with all the evidence and the defendants’ own experts, will be enough to raise a genuine issue of fact for trial. That question remains for Judge Cote to decide in a new analysis.

What Happens Now

The MDL is back. The cases are alive. But the fight is far from over.

Judge Cote must now conduct a new analysis and reconsider the three experts the Second Circuit found were wrongly excluded. She must weigh any new studies that have emerged since her 2023 ruling. The defendants will bring their own experts. They will fight every step of the way.

The question remains: will the admissible evidence, taken together with everything else, be enough to let these families reach a jury? The Second Circuit did not answer that. It only opened the door. What happens next depends on Judge Cote, on the science, and on the courage of the families who refuse to quit.

Now, hundreds of thousands of mothers of babies born with autism after they took Tylenol during their pregnancies can hold Johnson & Johnson and its successor entities selling Tylenol, Kenvue, Inc. and Kimberly Clark Corporation, responsible for the massive neurological damage suffered by their babies. These companies should be forced to pay for the damage they caused by failing to warn American women about this scientific link which company documents show was known only to them in private. Their secret was exposed. The government warned the public. The courts have reopened the cases. And these mothers will finally have their opportunity to seek justice.

Mikal Watts serves as one of three co-lead counsel for the MDL plaintiffs. He has fought for these families through every setback. He will keep fighting. Watts Law Firm LLP stands with those affected, pushing for accountability through every legal avenue available. We believe in the power of collective action to effect change and uphold the rights of consumers, especially when it concerns the health and future of our children.

This article is provided for informational purposes only and is not intended as legal advice. It is based on publicly available sources, including published court opinions and government websites. Reading this information does not create an attorney-client relationship with Watts Law Firm LLP or any of its lawyers. Legal outcomes depend on the specific facts of each situation, and businesses should consult their own counsel regarding questions about tariffs, potential refund claims, or any other legal matter.