President Donald Trump and Health and Human Services Secretary Robert F. Kennedy Jr. on Monday reportedly unveiled findings they say connect a widely used pain reliever to rising autism rates — and pointed to another drug that could provide relief for children already diagnosed.
“It was announced that the use of acetaminophen during pregnancy is tied to an increased risk of autism,” Trump said, referring to the active ingredient in Tylenol, one of the most commonly used medications in the world. “Taking Tylenol is not good. I’ll say it. It’s not good,” he told reporters, while noting that in cases of high maternal fever the drug might remain necessary. “There’s a lot of common sense in this.”
The announcement marks one of the most significant challenges yet to mainstream medical consensus on autism, which has surged in recent decades without a clear cause.
Kennedy, long an outspoken critic of public health orthodoxy, said HHS is also examining the role of vaccinations in the rising prevalence. Trump himself suggested what is often called a “delayed schedule” for childhood shots, spreading doses out over time.
Kenvue, the manufacturer of Tylenol, rejected the assertions. “We believe independent, sound science clearly shows that taking acetaminophen does not cause autism. We strongly disagree with any suggestion otherwise and are deeply concerned with the health risk this poses for expecting mothers,” the company said in a statement. The company’s stock has fallen about 15 percent since early September.
Alongside the warnings, Trump and Kennedy highlighted new research suggesting leucovorin, or folinic acid, could alleviate certain autism symptoms.
Though physicians would need to prescribe it for this purpose, early indications suggest that it may offer meaningful relief.
Dr. Marty Makary, the FDA commissioner, said public disclosure was essential. “We have an epidemic of autism that has increased 400% in the recent decades and we don’t have a known cause,” Makary told podcast host Georgia Howe. “Now this may be a cause, but when you have enough evidence to suggest an association and you have no other plausible cause, we have a duty to notify parents and doctors.”
Makary has already issued a “Dear doctor” letter to physicians nationwide. “We now have good data from large studies and the Harvard School of Public Health Dean has made a very conclusive statement that he believes the association is causal,” Makary explained. “So when you have that weight of evidence, you have to take it seriously and err on the side of safety, especially since the vast majority of low grade fevers do not need to be treated.”
On leucovorin, Makary said the century-old drug may address an overlooked dimension of autism. “Only recently have we recognized that some kids with autism actually have an autoimmune disease,” he said, describing how antibodies can block folate receptors in the brain, restricting critical nutrients despite adequate dietary intake.
Kennedy, who previewed these findings in April, warned then that autism affects one in 31 American children, nearly five times higher than when the CDC began tracking in 1992. Even more troubling, he said, many cases are severe. “25% of the kids diagnosed with autism are non-verbal, non-toilet trained, have other stereotypical features: head banging, tactile and light sensitivities, stimming, toe-walking, etc.”
Makary praised Kennedy for pressing questions that others shy away from. “Secretary Kennedy is asking questions that the American people are asking,” he said. “And so we have this odd new political landscape that’s penetrated science where you’re supposedly not allowed to ask certain questions. It’s created a tremendous amount of distrust. But I can tell you the purpose of science itself is to investigate questions.”
[READ MORE: Liberal Gov. Josh Shapiro Praises Charlie Kirk’s Commitment to Free Speech]
