Washington: President Donald Trump reignited controversy on Monday by repeatedly urging pregnant women and parents to avoid Tylenol, while reviving long-disputed claims that vaccines may contribute to autism. His remarks, made during a wide-ranging White House press conference, drew swift condemnation from medical experts who called the statements dangerous and misleading.

Trump’s warnings on Tylenol and vaccines

At the briefing, Trump said more than a dozen times, “Don’t take Tylenol,” while addressing pregnant women. He also cautioned against giving acetaminophen, Tylenol’s generic form, to infants and suggested that childhood vaccines administered too closely together could raise the risk of autism.

“Don’t let them pump your baby up with the largest pile of stuff you’ve ever seen in your life,” Trump said, later comparing routine immunisation schedules to “pumping into a horse.”

Although he stressed that he remained supportive of vaccines overall, Trump said shots should be spread out or given individually. “I think it’s very bad. They’re pumping, it looks like they’re pumping into a horse,” he added.

Administration announces autism initiatives

Alongside Trump, Health and Human Services Secretary Robert F. Kennedy Jr., a long-time vaccine sceptic, announced a new inter-agency effort to investigate potential causes of autism. FDA Commissioner Dr Marty Makary also said the agency was exploring approval of leucovorin, a folic acid metabolite, as a possible treatment for certain autism patients with folate deficiencies.

The administration also instructed the Food and Drug Administration to notify doctors that acetaminophen use “can be associated” with autism risk, though no evidence was provided to justify the step.

Experts push back

Medical professionals described Trump’s comments as reckless. Art Caplan, a bioethicist at New York University, called the press conference “the saddest display of a lack of evidence, rumours, recycling old myths, lousy advice, outright lies, and dangerous advice I have ever witnessed by anyone in authority.” 

The Society for Maternal-Fetal Medicine reiterated that acetaminophen remains an appropriate treatment for fever and pain in pregnancy. Dr Steven Fleischman, president of the American College of Obstetricians and Gynaecologists, warned that scaring expectant mothers with misinformation could do more harm: “Not treating the fever probably has more adverse effects that you need to worry about than taking the medication.”

The American Academy of Pediatrics also rejected Trump’s vaccine suggestions, stressing that “studies have repeatedly found no credible link between life-saving childhood vaccines and autism.”

Trump also insisted there was “no downside” to Americans heeding his advice "other than a mother will have to, as I say, tough it out a little bit” and avoid Tylenol for pain while pregnant. “Everything I said, there’s no downside to doing it," Trump said. "It can only be good.”

Kenvue Inc., the maker of Tylenol, dismissed any link between its product and autism. The company noted that untreated fevers can pose serious risks in pregnancy, forcing mothers into “a dangerous choice between suffering fevers or using riskier painkiller alternatives.”

Shares of Kenvue dropped 7.5% following Trump’s remarks, cutting the company’s market value by about $2.6 billion.

What is autism?

Autism spectrum disorder (ASD) is a developmental condition that affects individuals differently, often involving challenges with communication, social interaction, and learning. Some people experience profound autism, with significant intellectual disabilities and limited verbal skills, while many others live with milder forms.

Autism is not a disease and has no single cause. Research indicates a strong genetic basis, with hundreds of genes implicated. Environmental factors such as paternal age, preterm birth, or maternal health complications during pregnancy, including infections and fevers, may also play a role.

According to the US Centers for Disease Control and Prevention, autism now affects about 1 in 31 children, a significant increase from past decades. Experts attribute this rise primarily to broader diagnostic criteria and improved screening, not a surge in severe cases.

Evidence on Tylenol and autism

Some small studies have suggested that frequent acetaminophen use during pregnancy might be linked to autism, but many others have not confirmed such a connection. Researchers caution it is difficult to separate the drug’s impact from the effects of fever itself, which is already known to raise risks for pregnancy complications.

The Coalition of Autism Scientists noted that acetaminophen use in pregnancy has not risen in recent decades, while autism diagnoses have, further weakening claims of a causal link.

Despite his forceful language, Trump conceded his comments were not grounded in the medical consensus. “I’m just making these statements from me,” he said. “I’m not making them from these doctors.”

Doctors, however, warn that such rhetoric spreads confusion. As Dr Susan Kressly of the American Academy of Pediatrics put it: “Any effort to misrepresent sound, strong science poses a threat to the health of children.”

(With inputs from AP)