Tylenol-maker shares hit after report RFK Jr will suggest autism link

Tylenol-maker Kenvue has said its popular pain reliever is safe, as shares in the firm dropped sharply after a report that US Health Secretary Robert F Kennedy Jr would would potentially link autism to use of the medication in pregnancy.

Kenvue shares fell 14% before recovering slightly to end Friday trading down 9.5% as the firm spoke out to defend its over-the-counter drug.

The company has faced lawsuits for years alleging a possible link between autism and use of Tylenol, which is known as paracetamol in the UK.

The US Department of Health and Human Services said claims about the contents of its much-anticipated autism report were speculation.

According to the Wall Street Journal, Kennedy is expected to issue the findings this month, citing Tylenol use while pregnant as a potential cause of autism.

The newspaper said the federal report is expected to recommend a specific type of the vitamin folate as a way to treat the disorder.

The Department of Health and Human Services said in a statement to the BBC: “We are using gold-standard science to get to the bottom of America’s unprecedented rise in autism rates.”

US doctors typically recommend that pregnant women in need of pain relief take Tylenol, or another form of acetaminophen, rather than ibuprofen, which is sold as Advil.

Researchers have noted that acetaminophen is important for treating maternal fever and pain, which can also harm children.

Kenvue said in a statement: “We have continuously evaluated the science and continue to believe there is no causal link between acetaminophen use during pregnancy and autism.”

The company said leading medical organisations agreed on the safety of acetaminophen and its use during pregnancy.

It added: “We advise expecting mothers to speak to their healthcare professionals before taking any over-the-counter medications, including acetaminophen.”

The American College of Obstetricians and Gynecologists also recommends that pregnant women consult their doctors before using acetaminophen, as with all medicines.

Its chief of clinical practice, Christopher Zahn, said in a statement to Reuters news agency: “There is no clear evidence that proves a direct relationship between the prudent use of acetaminophen during pregnancy and fetal developmental issues.”

The US Food and Drug Administration has similar advice on its website.

Autism, which can lead to challenges in communication and social behaviour, affects an estimated one in 31 American children, according to a recent report from Centers for Disease Control and Prevention (CDC).

Kennedy – a vaccine sceptic – has long raised concerns about a rise of autism, but it is unclear whether the health department will blame inoculations in its forthcoming report.

“By September we will know what has caused the autism epidemic,” the health secretary said at a spring cabinet meeting with President Donald Trump.

Scientists attribute at least part of the rise in autism to increased awareness and an expanding definition of the disorder. Researchers have also been investigating environmental factors.

Studies on acetaminophen have been inconclusive as to any autism link.

Research last month by experts from Icahn School of Medicine at Mount Sinai and Harvard’s TH Chan School of Public Health analysed 46 previously published epidemiological studies.

They found that of these, 27 reported links between use of acetaminophen by pregnant women and an increased risk of neurodevelopmental disorders such as autism.

Another nine showed no significant link, while four others indicated protective effects.

Dr Nathaniel DeNicola, an OB-GYN who advises the American College of Obstetricians and Gynecologists, told the New York Times this study did not change much.

“The conclusion of the paper is that Tylenol should be used judiciously in the lowest dose, least frequent interval”, he said, adding that this was “exactly the current standard of care for Tylenol”.

In 2021, an international group of 91 scientists and clinicians published a consensus statement urging caution on use of the pain reliever during pregnancy.

But a 2024 study in the Journal of the American Medical Association involving 2.4 million children born in Sweden found no evidence to support a causal link.

Tylenol’s maker has faced hundreds of lawsuits claiming the medication can cause autism if mothers take it during pregnancy.

But last August, a US judge dismissed all the cases in federal court after finding that expert witnesses lacked scientific evidence for their claims.

The plaintiffs are challenging that ruling in a US appeals court.