Tylenol-maker Kenvue moved quickly on Friday to defend the safety of its best-selling pain reliever after a media report suggested the U.S. Health Secretary Robert F. Kennedy Jr. may link autism to acetaminophen use during pregnancy in an upcoming federal report.
Shares in Kenvue tumbled as much as 14% in early trading before closing down 9.5%, as investors reacted to speculation surrounding the report. The company has for years faced lawsuits alleging a connection between prenatal Tylenol use and autism, though courts have dismissed such claims for lack of scientific evidence.
According to The Wall Street Journal, the Department of Health and Human Services (HHS) is preparing to publish findings later this month that could cite acetaminophen, also known as paracetamol, as a potential factor in autism. The newspaper reported the draft recommendations may also include the use of a specific form of folate as a treatment.
HHS said any discussion about the report’s conclusions was premature. “We are using gold-standard science to get to the bottom of America’s unprecedented rise in autism rates,” the agency said in a statement to the BBC.
In a separate statement, Kenvue stressed there is “no causal link” between acetaminophen use in pregnancy and autism, noting that global health authorities continue to endorse its use when recommended by a doctor. “We advise expecting mothers to speak to their healthcare professionals before taking any over-the-counter medications, including acetaminophen,” the company said.
The American College of Obstetricians and Gynecologists (ACOG) echoed that view. Its chief of clinical practice, Christopher Zahn, told Reuters there is “no clear evidence that proves a direct relationship between the prudent use of acetaminophen during pregnancy and fetal developmental issues.” The U.S. Food and Drug Administration (FDA) offers similar guidance, urging women to consult physicians before using pain relievers while pregnant.
Autism spectrum disorder affects roughly one in 31 children in the United States, according to the Centers for Disease Control and Prevention (CDC). While Kennedy — a long-time vaccine sceptic — has linked rising autism rates to environmental and medical factors, scientists say much of the increase reflects broader diagnostic criteria and improved awareness.
Research into acetaminophen has produced mixed results. A 2021 international consensus statement urged caution, while a major 2024 Swedish study involving 2.4 million children found no evidence of a causal relationship. A review by Mount Sinai and Harvard researchers last month highlighted conflicting findings across 46 prior studies.
Kenvue continues to battle legal challenges despite a U.S. judge dismissing hundreds of autism-related lawsuits last year, ruling that plaintiffs’ experts failed to provide reliable scientific evidence. That decision is now under appeal.
With HHS expected to release its report in September, the debate over Tylenol’s safety during pregnancy is once again in the spotlight — leaving both parents and investors awaiting clarity.
