Trump links autism to the Tylenol ingredient acetaminophen during pregnancy
In this photo illustration, Tylenol capsules are seen on September 22, 2025 in San Anselmo, California.
Justin Sullivan | Getty Images
The Trump administration on Monday made an unproven link between autism and pregnant women’s use of acetaminophen, the active ingredient in one of the world’s most common over-the-counter painkillers. KenvueThis is Tylenol.
President Donald Trump said the Food and Drug Administration will issue a medical alert about the risk of patients taking acetaminophen during pregnancy unless they have a fever. The agency will also begin changing the safety labeling for acetaminophen on Tylenol and similar products.
These moves contradict much of the scientific literature, which does not suggest a causal link between autism and acetaminophen exposure in utero.
Many over-the-counter medications contain acetaminophen, but Tylenol is generally considered the safest treatment during pregnancy to relieve pain and fever as long as patients take the recommended dose.
“Taking Tylenol is not good,” Trump said during a news conference Monday. “They strongly recommend that women limit their use of Tylenol during pregnancy unless medically necessary. That means, for example, if you have an extremely high fever, you feel like you can’t take it, you can’t keep it up.”
The Department of Health and Human Services will encourage physicians to “use their best judgment” when using acetaminophen during pregnancy by prescribing “the lowest effective dose for the shortest duration necessary and only when treatment is necessary,” Department Secretary Robert F. Kennedy Jr. said during the press conference.
HHS will launch a nationwide campaign to inform patients about the alleged risk, Kennedy said.
In a statement on Monday, Kenvue said it believes in “independent, sound science” showing that taking paracetamol does not cause autism, and “we strongly reject any other suggestions and are deeply concerned about the health risk this poses to expectant mothers.” Without the drug as an option, women may have to suffer from conditions such as fever, which can be harmful to both them and their babies, or resort to riskier alternatives, Kenvue said.
According to the Society for Maternal-Fetal Medicine, untreated fever and pain during pregnancy can pose risks such as miscarriage, birth defects and high blood pressure for both mother and child.
FDA Commissioner Marty Makary suggested that treating fever “may prolong the duration of illness in a young child,” citing a Johns Hopkins study without providing further details.
“Perhaps this is because fever is the body’s natural way of getting rid of an infection,” Makary said.
Trump said several times during the briefing that “there is no downside” to not taking Tylenol during pregnancy or in the early years of a baby’s life.
FDA approves lesser-known drug
Also on Monday, the FDA approved a lesser-known drug, leucovorin, to treat autism, Dr. Mehmet Oz, Administrator of the Centers for Medicare & Medicaid Services, during the briefing.
The agency is specifically updating the labeling of leucovorin for cerebral folate deficiency, which HHS says is linked to autism. According to an HHS announcement, the change will allow children with autism to be treated with the drug and allow continued use if the children show linguistic, social or adaptive progress.
However, HHS said leucovorin is not a cure for autism and can only improve language deficits in a subset of children with the disorder. State Medicaid programs may cover the autism medication after the label is updated. The National Institutes of Health will also launch studies to confirm the effects of leucovorin on the disease, including studies on the drug’s safety.
Leucovorin is a form of folate, a B vitamin that is typically prescribed to counteract the side effects of some medications, including chemotherapy, and to treat vitamin B9 deficiency. Some early placebo-controlled clinical trials have shown that oral leucovorin, also called folinic acid, has the potential to improve symptoms in children with autism spectrum disorder.
The Food and Drug Administration released a notice early Monday that it was approving a version of Leucovorin previously made by GSK, the Wall Street Journal reported. But on Monday afternoon, the Federal Register website said it had received an “authority letter” requesting that the notice be retracted.
In a statement, a GSK spokesman said it does not intend to market Leucovorin. The company marketed the drug under the name Wellcovorin from 1983 to 1999, but the product was withdrawn from the market and has since been available as a generic. The spokesperson said changes to Wellcovorin’s label will help allow generics already on the market to incorporate this new approval for autism into their labeling.
Acetaminophen is the latest widely used and accepted treatment that has undermined Kennedy at the helm of the Department of Health and Human Services, which oversees federal health agencies that regulate drugs and other therapies. Kennedy has also taken steps to change vaccination policy in the US, amplifying false claims about safe and effective vaccinations using mRNA technology.
Kennedy has made autism a major focus of HHS, promising in April that the agency will “know what caused the autism epidemic” and eliminate exposures by September. He also said this month that the agency had launched a “massive testing and research effort” involving hundreds of scientists worldwide to determine the cause.
Much of the scientific community agrees that autism is due to a complex mix of genetic and environmental factors, making it unlikely that the disorder’s rising rates are due to a single cause.
Kennedy said HHS expects to make several announcements in the coming years informing parents about the underlying cause of autism and “potential pathways for prevention and reversal.” He acknowledged that autism is a complex disorder caused by a combination of factors and said HHS continues to examine other factors, such as vaccines.
“An area that we’re studying closely … about 40 to 70 percent of mothers with autism believe their child has been harmed by a vaccine,” Kennedy said. “President Trump believes we should listen to these mothers instead of putting our foot down like previous administrations have.”
Extensive research has debunked long-standing concerns that vaccines are linked to autism, a claim that Kennedy and other vaccine critics have made for several years.
Research on paracetamol use and autism
The Washington Post reported Friday that Trump administration officials have reviewed previous research indicating a link between taking acetaminophen during pregnancy and an increased risk of autism. The post says it includes an August report by Mount Sinai and Harvard researchers on 46 previous studies that suggest a link between prenatal exposure to the drug and an increased risk of neurodevelopmental disorders such as autism or attention deficit hyperactivity disorder, or ADHD.
The review found that the association was strongest when acetaminophen was taken for four weeks or longer, Dr. Andrea Baccarelli, one of the authors and dean of faculty at the Harvard TH Chan School of Public Health, in a statement. The review was funded by a grant from the National Institutes of Health.
“This biological evidence supports the possibility of a causal relationship between prenatal acetaminophen exposure and neurodevelopmental disorders, including autism,” Baccarelli said, adding that further research is needed to “confirm the association and determine causality.”
He said that based on the existing evidence, he believed that “caution should be exercised when using paracetamol during pregnancy – particularly heavy or prolonged use.” However, Baccarelli said acetaminophen remains an important tool for pregnant women and their doctors because the drug is the only approved medication for pain and fever relief during pregnancy.
He said that he and his colleagues recommend a “balanced approach based on the precautionary principle”: Patients who need fever or pain relief during pregnancy should take the lowest effective dose of the drug for the shortest possible duration, after consulting their doctor about the individual risks and benefits of this approach. Baccarelli said he discussed this recommendation and the review’s findings with NIH Director Jay Bhattacharya and Kennedy in recent weeks.
The researchers checked the results of the studies contradict other robust studies, including one published last year in the Journal of the American Medical Association that found acetaminophen use during pregnancy is not linked to autism, ADHD or intellectual disability. Researchers analyzed health records of 2.5 million children in Sweden.
When researchers initially looked at the general population, there was a very small increased risk of the disease in children whose mothers took the drug during pregnancy. However, researchers found no connection after comparing siblings within the same family: one was exposed to acetaminophen during pregnancy and the other was not.
On Monday before the announcement, the FDA’s website said the agency had found no “conclusive evidence” that appropriate use of acetaminophen during pregnancy causes “adverse effects on pregnancy, birth, neurobehavioral, or development.” The American College of Obstetricians and Gynecologists maintains that acetaminophen is safe during pregnancy when taken as directed and after consulting a doctor.
Some parents have filed lawsuits claiming they gave birth to children with autism after taking the painkiller.
But a federal judge in Manhattan ruled in 2023 that some of those lawsuits lacked scientific evidence and ended the litigation later in 2024.
—CNBC’s Angelica Peebles contributed to this report.
