What the science says about Tylenol and autism link as RFK Jr. releases bombshell report

President Trump has urged pregnant women to updating labels on acetaminophen packaging to include a warning.

The new recommendations come in response to research that shows a potential link between acetaminophen use and autism — yet The American College of Obstetricians and Gynecologists (ACOG) maintains that acetaminophen is safe for pregnant women.

That’s because the science isn’t exactly clear-cut — and most experts are calling for more research to be done before, including the very researchers who have demonstrated the link.

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The changes come from a new report from Robert F. Kennedy Jr.’s Department of Health and Human Services.

“We are using gold-standard science to get to the bottom of America’s unprecedented rise in autism rates,” an HHS spokesperson told The Post earlier this month.

Trump has embraced the new recommendations, telling reporters at the White House on Monday, “With Tylenol, don’t take it! Don’t take it.

“Ideally, you don’t take it all, but if you have to, if you can’t tough it out, if there’s a problem, you’re going to end up doing it.”

The recommendations seem to be in part based on a study analysis led by the Icahn School of Medicine at Mount Sinai, which determined that when children are exposed to acetaminophen in vitro, they could be more likely to develop neurodevelopmental disorders like autism and ADHD.

But even the scientists behind the research caution that the study does not prove that acetaminophen causes autism — and they aren’t telling women to stay away.

What is autism?

It’s a complex disorder that affects brain development, resulting in differences in social communication as well as repetitive behaviors and focused interests.

are on the rise, with diagnoses in the US jumping 175% between 2011 and 2022.

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Extensive evidence suggests that interactions between genetic and environmental factors are key to the development of autism.

These factors may include advanced parental age, infections during pregnancy, birth complications, a premature baby or one with lower-than-expected fetal growth or use of certain medications while pregnant.

What is acetaminophen?

It’s an over-the-counter medication designed to relieve mild to moderate pain and reduce fever, though scientists aren’t exactly sure how it works.

It’s most famously sold as Tylenol. It’s also known as paracetamol outside the US. Acetaminophen is widely used to treat maternal fever and pain.

What do the studies say?

A 2024 study of nearly 2.5 million Swedish children found no causal link between prenatal use of acetaminophen and neurodevelopmental disorders like autism or attention deficit hyperactivity disorder (ADHD).

The Icahn School of Medicine at Mount Sinai led a 2025 analysis of 46 studies that did identify a potential link to an increased risk of these conditions.

The researchers warned that acetaminophen may trigger oxidative stress, interfere with hormones and cause genetic changes that disturb fetal brain development, but cautioned that more research is needed to establish a causal relationship.

In a statement to The Post, Mount Sinai Health System, noted that the study found an association between prenatal acetaminophen exposure and increased risk of autism spectrum disorder — but not a causal link, meaning not proof that once caused the other.

“We recommend judicious acetaminophen use — lowest effective dose, shortest duration — under medical guidance, tailored to individual risk-benefit assessments, rather than a broad limitation,” the researchers wrote last month in BMC Environmental Health.

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Study lead author Andrea Baccarelli, MD, PhD also noted in a statement that the association is strongest when pregnant women take the drug for four weeks or longer.

“At the same time, as the only approved medication for pain and fever reduction during pregnancy, acetaminophen remains an important tool for pregnant patients and their physicians,” he said. “High fever can pose risks to both the mother and the fetus, including neural tube defects and preterm birth.”

One theory is that any potential link may be due to the underlying conditions that caused the mother to take the acetaminophen.

The American College of Obstetricians and Gynecologists (ACOG) maintains that acetaminophen is safe for pregnant women, though it advises all expectant mothers to consult with their doctor before taking any medication.

For its part, a spokesperson for Tylenol-maker Kenvue told the WSJ that it “continues to believe there is no causal link between acetaminophen use during pregnancy and autism.”

Kenvue’s shares fell more than 14% on Friday after the WSJ published its report.

Many Tylenol-related lawsuits claiming links to autism have been dismissed due to a lack of credible scientific evidence supporting the claims.