WASHINGTON - Health Secretary Robert F. Kennedy Jr. said Oct. 29 that he does not have "sufficient" evidence to link Tylenol to autism, more than a month after the White House discouraged the medicine's use by pregnant women and young children.

Evidence does not show that Kenvue's pain medicine Tylenol definitively causes autism but that it should still be used cautiously, President Donald Trump's top health official told reporters. Last month the president said U.S. health officials would recommend limiting Tylenol's use.

Kennedy's comments also come one day after the Republican state of Texas sued Kenvue, the maker of the medicine also known as acetaminophen and which has been sold widely for decades.

"The causative association . . . between Tylenol given in pregnancy and the perinatal periods is not sufficient to say it definitely causes autism. But it is very suggestive," Kennedy told reporters, citing animal, blood and observational studies.

"There should be a cautious approach to it," he added.

Asked if Kennedy's latest comments signaled a softening of his stance on the issue, Emily G. Hilliard, Health and Human Services press secretary, said: "It’s the same position the Secretary has had since the beginning."

In a report April 15, the Centers for Disease Control and Prevention found that in 2022, 1 in 31 children were diagnosed with autism by age 8 in the United States, an increase from 1 in 36 children in 2020. The prevalence of autism among boys was 1 in 20, and the 2022 rate is five times higher than it was in 2000.

In August, Kennedy said a study on autism he spearheaded in April had found “interventions” that could be causing the neuro-developmental disorder.

A month later, Trump and Kennedy, neither of whom are doctors, held a press conference in September to specifically warn pregnant women against taking the medication without citing any scientific evidence.

“Don’t take Tylenol,” Trump said repeatedly during a Sept. 22 news conference alongside Kennedy. “Fight like hell not to take it.”

On Oct. 26, as he was en route to Asia, Trump chimed in once again, on Truth Social: "Pregnant Women, DON’T USE TYLENOL UNLESS ABSOLUTELY NECESSARY, DON’T GIVE TYLENOL TO YOUR YOUNG CHILD FOR VIRTUALLY ANY REASON."

Kennedy has couched his statements by saying there was no clear scientific evidence showing causation: During a Cabinet meeting on Oct. 9 with Trump, Kennedy said: "Anybody who takes the stuff during pregnancy unless they have to, is irresponsible. It is not proof. We’re doing the studies to make the proof."

The Food and Drug Administration announced on Sept. 22 that it would "issue a physician notice and begin the process to initiate a safety label change for acetaminophen, the active ingredient in Tylenol and other such drugs.

"The FDA is responding to prior clinical and laboratory studies that suggest a potential association between acetaminophen use during pregnancy and adverse neurodevelopmental outcomes," the agency said in its announcement. "FDA also recognizes that there are contrary studies showing no association and that there can be risks for untreated fever in pregnancy, both for the mother and fetus. "

The Department of Health and Human Services said "given the conflicting literature and lack of clear causal evidence" it was encouraging clinicians to "exercise their best judgment."

Kennedy's unproven claim initially hit shares of Kenvue, a consumer health company, which was spun off from Johnson & Johnson in 2023. The claim also prompted pushback from many doctors.

Kenvue has repeatedly defended the pain medicine, saying there is no scientific link to autism and warning that such suggestions could endanger maternal health.

The company has urged the U.S. Food and Drug Administration to reject the call for an autism warning on Tylenol's label, and has reportedly hired a new marketing chief.

"We agree, as Secretary Kennedy said, that the best message to pregnant women is to consult their healthcare professional before taking acetaminophen, which is what our Tylenol label tells consumers to do. We also agree that there is no definitive causative association between taking acetaminophen and autism," the company said in a statement.

Kenvue shares were down 1.4% at market close on Oct. 29.

Contributing: Reuters

This article originally appeared on USA TODAY: Health Secretary Kennedy says there's 'not sufficient' proof to show Tylenol causes autism

Reporting by Swapna Venugopal Ramaswamy, USA TODAY / USA TODAY

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