(Bloomberg/John Tozzi and Rachel Cohrs Zhang) — Trump administration officials plan to link the active ingredient in Tylenol to autism Monday, the Washington Post reported, citing unnamed people familiar with the matter.

Officials plan to warn pregnant women against using the medication, one of the world’s most common, over-the-counter pain relievers, unless they have a fever, the paper said.

An earlier report that the administration was investigating potential links between acetaminophen and autism sent shares of Tylenol-maker Kenvue Inc. sinking.

Kenvue said Sunday that “independent, sound science” shows taking acetaminophen does not cause autism.

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“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 facts are that over a decade of rigorous research, endorsed by leading medical professionals and global health regulators, confirms there is no credible evidence linking acetaminophen to autism.”

Kenvue shares fell as much as 5.9% in New York trading on Monday. The stock has slumped 19% this year.

The Washington Post said the Trump administration will promote another drug, leucovorin, as a potential autism treatment. Leucovorin, a generic medication made by several manufacturers, is typically used in cancer treatment to counter the harmful side effects of other drugs.

‘Found an Answer’

The report comes as President Donald Trump said he’d hold what he called “one of the most important news conferences” he’ll ever have on Monday regarding autism.

“We think we found an answer to autism,” Trump said during a memorial ceremony for conservative activist Charlie Kirk. “There’s obviously something really wrong, we think we know what that is.”

In late 2023, a judge rejected the scientific evidence behind the lawsuits alleging prenatal exposure to over-the-counter Tylenol caused autism.

US District Judge Denise Cote in Manhattan concluded that plaintiffs in more than 400 suits against makers and sellers of acetaminophen relied on flawed science in seeking to prove an increased risk of developmental issues in babies.

(Corrects description of Tylenol in photo caption in the web version of story.)

A subsequent study published in 2024 that analyzed the records of nearly 2.5 million siblings born in Sweden from 1995 through 2019 found no increased risk of autism when their mothers took acetaminophen while pregnant.

–With assistance from Jennifer A. Dlouhy, María Paula Mijares Torres, Jessica Nix, Madison Muller and Subrat Patnaik.

(Updates with shares trading in sixth paragraph.)

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