- The Trump administration believes evidence shows autism is linked to use of acetaminophen early in pregnancy.
- Health and Human Services agencies are putting lots of research into understanding and preventing autism.
- The administration may also suggest that a drug that protects against cancer drug could treat autism.
During what he’d promised would be an “important announcement,” President Donald Trump on Monday linked autism to use of Tylenol and other acetaminophen-based products in pregnancy.
The president and Health and Human Services Secretary Robert F. Kennedy Jr. also said that a drug to counter certain cancer treatments effects could help treat autism.
The president cited a review of previous research conducted by Mount Sinai and Harvard researchers that found a potential association between acetaminophen use early in pregnancy and increased risk of autism in children. The researchers suggested Tylenol and similar products should not be used early in pregnancy except in the case of fever.
Trump went a step further during a news conference, telling those who are pregnant, “Don’t take it,” which he repeated several times. For those who absolutely “can’t tough it out,” he recommended using the lowest dose possible for the least amount of time.
He said the U.S. Food and Drug Administration would soon notify physicians that the agency is “strongly recommending that women limit Tylenol use during pregnancy unless medically necessary.”
Leucovorin is the possible treatment touted during the press event. It’s usually prescribed to counteract some cancer medication side effects and to treat a vitamin B9 deficiency. “Early double-blind, placebo-controlled trials administering leucovorin to children with autism have shown what some scientists describe as remarkable improvements in their ability to speak and understand others,” per the The Washington Post.
Outside North America, acetaminophen is called paracetamol.
The review of studies Trump pointed to that finds a potential link between autism and acetaminophen was published in July in the journal Environmental Health. It noted that acetaminophen is the most commonly used nonprescription pain and fever medication during pregnancy. “Appropriate and immediate steps should be taken to advise pregnant women to limit acetaminophen consumption to protect their offspring’s neurodevelopment,” the researchers wrote.
They said their research found a “strong, consistent association between prenatal acetaminophen exposure” and neurodevelopmental issues, but added that because of study limitations, they could not prove “definitive causation.” Per the researchers, “We advocate cautious, time-limited acetaminophen use under medical guidance, highlighting the need for research into safer alternatives and updated guidelines.”
Going after the causes of autism
The NIH has been tasked by the president and Kennedy with studying autism and during the press conference it was announced that 13 teams out of a couple hundred that applied have received grants to study the causes and treatments of autism — and to verify past findings.
Couching the belief that acetaminophen is linked to autism as a “potential association,” Kennedy promised transparency regarding findings. “We are now replacing the institutional culture of politicized science and corruption with evidence-based medicine.” He said in the past that the National Institutes of Health “has focused almost solely on politically safe and entirely fruitless research about the genetic drivers of autism.” He added that at the president’s direction, he has fast-tracked research on autism.
The administration touting a potential link to acetaminophen was somewhat surprising, as Kennedy has repeatedly linked vaccines to autism. Last week, Dr. Robert Malone, a new member of the Centers for Disease Control and Prevention’s vaccine advisory committee, told One America News Network he believed Kennedy would link all three: Tylenol, vaccinations and autism.
And he and the president did, both talking about the complexity and likelihood that different factors led to neurological issues. Kennedy had pledged that the urgent push for answers would yield some findings by September. He also said that “we will regularly update the public about our progress.”
Fever or pain in pregnancy
Pregnant women have been told for years that in case of fever or pain, Tylenol and generic acetaminophen are the safest over-the-counter options. Advil and generic ibuprofen have been linked to birth defects and risk of miscarriage.
Kenvue, which makes Tylenol, said by email to NBC before the formal announcement that “nothing is more important to us than the health and safety of the people who use our products. We have continuously evaluated the science and continue to believe there is no causal link between acetaminophen use during pregnancy and autism.”
Kenvue told BBC in a statement that “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.”
What we know about autism
Autism spectrum disorder covers a range of symptoms, from mild to severe, that impact social communication and language development. Repetitive behavior is also typically an aspect of the disorder.
It has been widely believed that autism is caused by a complex mix of genetic and environmental factors. The Post reported that “some experts had recently considered (autism) predominantly genetic and therefore largely untreatable.”
The CDC said this spring that autism rates have been increasing dramatically. In 2000, 1 in 150 U.S. children at age 8 were diagnosed with autism; in 2022, the share had increased to 1 in 31.
Some believe cases haven’t increased that much, but instead that experts are becoming better at identifying autism spectrum disorder.
As Politico noted, “Kennedy believes environmental factors are causing the rise in autism cases — despite ample evidence to the contrary, he suspects vaccines are involved — while many public health experts believe it’s because of changing diagnostic criteria and more attention to the condition.“
The American College of Obstetrics and Gynecology has deemed acetaminophen safe for pain relief in pregnancy.
“Studies that have been conducted in the past show no clear evidence that proves a direct relationship between the prudent use of acetaminophen during any trimester and fetal developmental issues,” the group said in a consensus statement in 2021. “Neurodevelopmental disorders, in particular, are multifactorial and very difficult to associate with a singular cause.” The statement said that since brain development is ongoing for some time, it “leaves room for children to be exposed to a number of factors that could potentially lead to these issues.”
The science has gone both ways. JAMA Network in April published an international study by researchers in Stockholm, Sweden, and in Philadelphia that looked at use of the fever-reducing drug as a risk factor for autism, attention deficit/hyperactivity disorder and intellectual disability.
Initially, the researchers found “marginally increased risk of autism and ADHD associated with acetaminophen use during pregnancy.” When they analyzed matched sibling pairs, they found no such risk associated with autism, ADHD or intellectual disability from acetaminophen use.
“This suggests that associations observed in other models may have been attributable to confounding,” they wrote.
Confounding refers to a “spurious association,” per Oxford. Things appear to be linked but there’s actually something else that’s not identified going on.
Dr. Brian Lee, a professor of epidemiology and biostatistics at Drexel University, who was involved in the study, confirmed they saw a slight increase in autism in offspring of acetaminophen users. But when they looked at sibling pairs, that increase “flatlined,” he told media in a briefing early Monday evening.
He said they looked at 2.5 million pregnancies and followed them for up to 20 years in what he calls a “kind of an apples to oranges comparison” because moms who took acetaminophen are sicker, with a medical condition that needs treatment, such as infections, fevers and pregnancy-related pain. He called the genetic link to neurodevelopmental disorders “the elephant in the room,” since he said autism is often inherited. He noted that looking at acetaminophen users vs. non-users “sort of ignores that aspect.”
What is leucovorin?
Leucovorin is a cancer and anemia drug that the Trump administration touts as a possible treatment for autism, too. Leucovorin is a form of vitamin B9, which is commonly called folate.
Kennedy called it “an exciting therapy that may benefit large numbers of children who suffer from autism.” He said that “peer-reviewed literature has documented that up to 60% of folate deficient children with ASD can have improved verbal communications if given leucovorin. I have instructed NIH FDA and CMS to help doctors treat children appropriately.”
According to Medline Plus, leucovorin is used to prevent “harmful effects of methotrexate” when that cancer chemotherapy medication is used. It belongs to a class of medications called folic acid analogs and “works by protecting healthy cells from the effects of methotrexate or similar medications, while allowing methotrexate to enter and kill cancer cells.”
The Washington Post reports there’s real, but “fragile” hope in using leucovorin to treat autism. The article tells the story of Nathaniel Schumann, who at 8 had autism and was nonverbal. The story said that two weeks after he first received the study pill, he spoke in full sentences.
The article said that studies have shown those with autism have trouble transporting folate to the brain and it is essential for brain development. The belief is leucovorin may help with its delivery.
But researchers are calling for more study and Richard Frye, a pediatric neurologist who studies the drug, said he’s hopeful it will help, but the research is still early.
The Autism Science Foundation said more studies are needed and that it’s too soon to recommend it to treat autism.
“I don’t think you should go out and use it right now based on the body of evidence that exists, but it’s certainly worthy of further exploration,” Scott Gottlieb, a former FDA commissioner, said in an interview on CNBC’s “Squawk Box” on Monday.