President Donald Trump claimed Monday that acetaminophen, the main ingredient in Tylenol, is linked to autism, despite experts warning that studies on this question are mixed, and no publicly released study shows Tylenol is a direct cause.
Speaking from the White House, where he was joined by Health and Human Services Secretary Robert F. Kennedy Jr., among others, the president told reporters that the U.S. Food and Drug Administration would begin notifying physicians immediately of its recommendation that pregnant women should avoid taking Tylenol during pregnancy unless absolutely necessary. He added that the FDA would update the label for acetaminophen with additional information and language about the purported risk.
The administration also announced Monday that it is starting an approval process for a drug called leucovorin to potentially treat autism, despite limited evidence of benefit.
An official told ABC News prior the event that the president was set to announce “historic progress” on his pledge “to address America’s rising rate of autism.”
Scientific studies examining the potential link between Tylenol use during pregnancy and autism or ADHD rates have produced inconclusive results in the past, and experts have said research into leucovorin as a treatment is preliminary.
In the wake of the announcement, major medical groups pushed back, saying Tylenol is the safest painkiller during pregnancy and warning that Trump’s strong language could discourage women from using it, even when it is medically advised.
Autism diagnoses have continued to increase in recent years with an estimated 1 in 31 8-year-old children receiving an autism diagnosis in 2022, according to a 2025 report from the U.S. Centers for Disease Control and Prevention.
Medical experts told ABC News previously that the increase in autism diagnoses is in large part due to better awareness, better access to screening and services, and a widening of the definition of the spectrum and the types of symptoms associated with the disorder.
Here’s what parents or prospective parents should know about the president’s comments regarding autism and supposed links to the popular pain reliever.
What did Trump say about autism and Tylenol?
Trump warned against the use of Tylenol during pregnancy during Monday’s event, which was also attended by members of his administration.
“They are strongly recommending that women limit Tylenol use during pregnancy unless medically necessary,” Trump said, referring to the FDA. “That’s, for instance, in cases of extremely high fever.”
Speaking directly to pregnant people, he added, “Don’t take Tylenol. There’s no downside. Don’t take it. You’ll be uncomfortable. It won’t be as easy, maybe. But don’t take it if you’re pregnant. Don’t take Tylenol, and don’t give it to the baby after the baby is born.”
Trump also said at times he was offering his own opinion, as opposed to scientific research.
“You know, I’m just making these statements from me,” he said. “I’m not making them from these doctors, because when they talk about, you know, different results, different studies, I talk about a lot of common sense. And they have that too. They have that too, a lot.”
Speaking with ABC News on Monday, FDA Commissioner Dr. Marty Makary claimed acetaminophen had been “given willy-nilly, way too frequently, without any discussion of the potential risks … to balance out those discussions about the potential benefit.”
“We’re just saying we want this body of scientific evidence now to be a part of that informed consent so that individuals can engage in proper shared decision making,” he added.
What do prior scientific studies say about the link between Tylenol use during pregnancy and autism?
Scientific studies attempting to answer the question of whether or not Tylenol use during pregnancy is associated with increased autism or ADHD rates have produced inconclusive results.
Some studies have suggested there could be a possible link, but these studies stop short of showing cause and effect. Other similar large studies show no such link.
During Monday’s press conference, federal officials cited an August 2025 meta-analysis from researchers at Mt. Sinai, the Harvard T.H. Chan School of Public Heath, UCLA’s Fielding School of Public Health and UMass Lowell, which showed an association between prenatal exposure to acetaminophen and diagnoses of neurodevelopmental disorders, including autism and ADHD, in children.
The authors of the meta-analysis, which looked at 46 studies, refuted the idea that their work proved Tylenol taken during pregnancy causes autism, and did not recommend that pregnant patients stop using Tylenol.
“[A]s the only approved medication for pain and fever reduction during pregnancy, acetaminophen remains an important tool for pregnant patients and their physicians,” co-author Dr. Andrea Baccarelli, dean of the faculty and professor of environmental health at Harvard T.H. Chan School of Public Health, told ABC News in a statement. “High fever can pose risks to both the mother and the fetus, including neural tube defects and preterm birth.”
What do scientific studies say about leucovorin as a treatment for autism?
The Trump administration also announced Monday that it was starting the approval process for a drug called leucovorin as a possible treatment for autism.
Leucovorin, which is typically used as part of cancer care, has shown early promise in a handful of small studies suggesting it may help the symptoms of some children with autism.
Experts caution, however, that there is no public conclusive evidence to support those statements.
“I see a very murky picture, and it’s really hard to say anything more than ‘We should continue studying this in controlled trials,'” Dr. Kevin Klatt, a registered dietitian and a postdoctoral fellow at Baylor College of Medicine, said in a statement to ABC News.
He added, “We should not be blasting it to the public and providing false hope.”
What do non-governmental medical organizations say about the potential link between autism and Tylenol?
The American College of Obstetricians and Gynecologists, a group of physicians specializing in obstetrics and gynecology, and other major medical groups have maintained that acetaminophen is the safest painkiller and fever reducer during pregnancy.
Following Trump’s announcement, Dr. Steven Fleischman, president of the ACOG, doubled down on the organization’s assertion that Tylenol is safe in pregnancy.
“Suggestions that acetaminophen use in pregnancy causes autism are not only highly concerning to clinicians but also irresponsible when considering the harmful and confusing message they send to pregnant patients, including those who may need to rely on this beneficial medicine during pregnancy,” Fleischman said in a statement.
“Today’s announcement by HHS is not backed by the full body of scientific evidence and dangerously simplifies the many and complex causes of neurologic challenges in children,” Fleischman continued. “It is highly unsettling that our federal health agencies are willing to make an announcement that will affect the health and well-being of millions of people without the backing of reliable data.”
The American Academy of Pediatrics said in a separate statement that Monday’s White House announcement was “filled with dangerous claims and misleading information that sends a confusing message to parents and expecting parents” and also pushed back against additional claims Trump made linking vaccines to autism.
“Regarding autism, we know it is complex, highly variable and increasingly linked to genetics,” the AAP said. “There is no single, root cause of autism, and there is no single medication that will give every autistic child or adult what they need.”
The American Psychiatric Association similarly pushed back on Trump’s claims, reiterating the safety and effectiveness of acetaminophen.
“Autism is a complex disorder, and it is incorrect to imply that a handful of studies have established causation. A strong base of evidence shows that acetaminophen, when taken as directed, is safe for use during pregnancy. Any decisions around a course of treatment should be determined by a patient and their doctor,” the APA stated.
It added, “Leucovorin … has not been a recommended treatment for autism. It will require many more years of research before we know if leucovorin is an appropriate treatment for individuals with autism.”
The Coalition of Autism Scientists also pushed back Monday on the information presented by the Trump administration, labeling it as fear-inducing.
“The data cited do not support the claim that Tylenol causes autism and leucovorin is a cure, and only stoke fear and falsely suggest hope when there is no simple answer,” the group said.
Are any changes planned based on Trump’s remarks?
The Trump administration said Monday it would work to update the label for acetaminophen, commonly known as Tylenol, to add language about its purported risks.
“Today, the FDA will issue a physician’s notice about the risk of acetaminophen during pregnancy and begin the process to initiate a safety label change,” Kennedy said, speaking from the White House.
He added that his department would “launch a nationwide public service campaign to inform families and protect public health.”
The FDA released a note to doctors Monday evening, addressing possible links between acetaminophen during pregnancy and autism. However, it stated there has been no evidence that Tylenol causes autism, and the association is an ongoing area of scientific debate.
“While an association between acetaminophen and autism has been described in many studies, a causal relationship has not been established and there are contrary studies in the scientific literature,” the note read.
HHS officials also issued a press release on Monday stating that the agency had “initiated the approval of leucovorin calcium tablets for patients with cerebral folate deficiency (CFD), a neurological condition that affects folate (a vitamin essential for brain health) transport into the brain.”
“Individuals with cerebral folate deficiency have been observed to have developmental delays with autistic features (e.g., challenges with social communication, sensory processing, and repetitive behaviors), seizures, and problems with movement and coordination,” the press release read.
What do experts believe causes autism?
ASD, or autism spectrum disorder, is a developmental disability caused by differences in the brain, according to the CDC.
People with ASD often communicate, interact, behave and learn differently, the CDC states. ASD symptoms typically begin before age 3 and can last a lifetime, although symptoms may change over time.
While there is no known single cause of the disorder, scientists have been researching autism for decades and now understand that for many people, genetics likely play a role. Some studies suggest that factors such as older reproductive age and environmental risk factors could play a role.
The makers of Tylenol say it does not cause autism
“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,” Kenvue, the maker of Tylenol, said in a statement to ABC News on Sunday.
The statement went on to describe acetaminophen as “the safest pain reliever option for pregnant women as needed throughout their entire pregnancy.”
Kenvue said the company stands “with the many public health and medical professionals who have reviewed this science” and “will continue to explore all options to protect the health interests of American women and children.”