Written and Reviewed By: Vikas Londhe MPharm
Global health authorities, including the FDA, HHS, and WHO, are reviewing evidence on a possible link between acetaminophen (Tylenol) use during pregnancy and autism. Learn what official statements say, current research findings, and how the controversy is being addressed worldwide.
Acetaminophen, also known as paracetamol and commonly sold under the brand name Tylenol in the United States, is widely used for pain and fever and is the drug of choice for these conditions during pregnancy. For decades, it has been considered safe when taken at recommended doses. In September 2025, the U.S. Food and Drug Administration (FDA) announced it would begin updating acetaminophen labeling to reflect evidence suggesting a possible association between prenatal use and neurodevelopmental conditions such as autism and ADHD. A White House statement amplified the message, sparking public concern and debate.
On September 22, 2025, the FDA issued a press release and a Notice to Physicians. The agency stated that some studies suggest an association between acetaminophen use during pregnancy and increased risk of autism spectrum disorder and ADHD in children. While emphasizing that causation has not been proven, the FDA recommended clinicians to weigh risks and benefits, particularly when prescribing or advising prolonged use.
Following to this press release, the White House and Department of Health and Human Services (HHS) released statements framing acetaminophen as a potential contributor to the autism “epidemic.” This political framing pulled strong reactions from the medical community, who argued that the science remains uncertain.
FDA Actions
The FDA issued a Notice to Physicians recommending caution with acetaminophen use during pregnancy; the FDA has pointed out some facts, such as:
- Acetaminophen use by pregnant women has been associated with an increased risk of neurological conditions like autism and ADHD.
- Some studies show that chronic use of acetaminophen during pregnancy augments the risk.
- The risk is prominent because the liver of the fetus is still developing during pregnancy, and it is not able to metabolize acetaminophen properly.
However, the causal relationship is not yet confirmed, but in the spirit of patient safety, clinicians should consider low-dose acetaminophen in pregnancy for low-grade fever. At the same time, the agency also emphasizes that low-grade fever in pregnant women and children does not always require medication.
The agency plans a labeling update to inform clinicians and patients of potential risks while acknowledging conflicting studies and lack of causal proof.
HHS and White House Announcement
The Trump administration and HHS have been tracking rising autism rates in the U.S. for several years. As administration are concerns about environmental, nutritional, and prenatal factors including the potential impact of medications like acetaminophen and leucovorin prompted a review of existing scientific evidence. In September 2025, the FDA issued a formal Notice to Physicians highlighting studies suggesting an association between prenatal acetaminophen use and neurodevelopmental outcomes, such as autism and ADHD. This official guidance, together with long-standing federal efforts to understand and address the autism epidemic, provided the foundation for the broader initiatives announced by HHS and the White House.
Overview of the Autism Epidemic
Prevalence Increase: Autism Spectrum Disorder (ASD) diagnosis has surged about 400% since 2000, now affecting 1 in 31 American children.
Disproportionate Impact: Boys are more frequently diagnosed, with a rate of 1 in 20.
These statistics underscore the urgent need for comprehensive action to understand and address the factors contributing to the rise in ASD diagnosis.
Leucovorin as a Potential Treatment
Cerebral Folate Deficiency (CFD) is a neurological condition where the brain lacks sufficient folate, leading to severe developmental issues, including autistic symptoms.
U.S. Food and Drug Administration (FDA) has issued a Federal Register notice to update the labeling for leucovorin, a form of folate, to include its use in treating CFD associated with ASD.
The National Institutes of Health (NIH) will initiate confirmatory trials and safety studies to assess the broader impact and efficacy of leucovorin in treating ASD symptoms.
Acetaminophen Use during Pregnancy
The FDA will begin the process of updating safety labels for acetaminophen (Tylenol and similar products) to inform healthcare providers and patients about potential risks associated with its use during pregnancy.
HHS will launch a nationwide public service campaign to educate families about the potential neurodevelopmental risks linked to prenatal acetaminophen exposure.
Because the evidence is inconsistent and causation is not proven, healthcare providers should use their judgment. They should give acetaminophen at the lowest effective dose and for the shortest time needed during pregnancy.
Key opinions from officials
Following the recent announcement by President Donald J. Trump and Health and Human Services (HHS) Secretary Robert F. Kennedy Jr. regarding the potential link between prenatal acetaminophen use and autism, several key health officials have provided statements clarifying their positions and the administration’s approach.
Commissioner of the U.S. Food and Drug Administration (FDA) Dr. Marty Makary acknowledged that while some studies suggest an association between acetaminophen use during pregnancy and neurodevelopmental conditions such as autism and ADHD, a definitive causal link has not been established. He emphasized that the FDA plans to update safety labels for acetaminophen products to reflect these concerns, advising healthcare providers to exercise caution and consider the lowest effective dose for the shortest duration when prescribing the medication during pregnancy
Dr. Jay Bhattacharya, Director of the National Institutes of Health (NIH), expressed support for the administration’s focus on autism research. He highlighted the NIH’s commitment to funding studies that explore the complex factors contributing to the rise in autism diagnosis. Dr. Bhattacharya noted that the NIH is prioritizing research that examines environmental exposures, genetic predispositions, and other potential contributors to autism spectrum disorder
Dr. Mehmet Oz, Administrator of the Centers for Medicare & Medicaid Services (CMS), took a more measured stance, publicly dissociating himself from President Trump’s assertion that pregnant women should avoid acetaminophen entirely. In a recent interview, Dr. Oz stated that while the evidence is not definitive, acetaminophen is likely safe when used appropriately, particularly for managing high fever during pregnancy. He emphasized the importance of balancing potential risks with the benefits of treating maternal health conditions.
WHO Position on Acetaminophen Use during Pregnancy
WHO acknowledged the increasing global prevalence of ASD, now affecting approximately 62 million people worldwide. WHO acknowledges that some studies have investigated potential links between prenatal acetaminophen use and neurodevelopmental outcomes such as autism. However, WHO emphasizes that the evidence is inconclusive, and no causal relationship has been established. The organization advises that pregnant women should follow professional medical guidance when using any medication, including acetaminophen, and use the lowest effective dose for the shortest necessary duration. This approach aligns with WHO’s broader commitment to evidence-based maternal and child health practices.
The debate over acetaminophen use in pregnancy and its possible link to autism reflects the intricacy of balancing maternal health needs with emerging safety concerns. While some observatory studies have suggest an association but the evidence remains inconclusive, and no direct causal relationship has been confirmed.
Global health authorities have taken cautious but distinct positions on this issue. The FDA has advised physicians to limit acetaminophen use during pregnancy and is moving toward updated labeling. The HHS and Trump administration have launched broader autism initiatives, combining research funding, regulatory changes, and public awareness campaigns. The NIH has committed to large-scale studies. The WHO has stated that the evidence linking acetaminophen to autism is inconclusive and continues to recommend its careful, short-term use under medical guidance.
At Pharmacally, we are closely following these developments. We will continue to report updates as more data, regulatory actions, and expert recommendations emerge.
References
FDA Responds to Evidence of Possible Association between Autism and Acetaminophen Use during Pregnancy, US FDA, 22 September 2025, https://www.fda.gov/news-events/press-announcements/fda-responds-evidence-possible-association-between-autism-and-acetaminophen-use-during-pregnancy
Notice to Physicians on the Use of Acetaminophen during Pregnancy, USFDA, 22 September 2025, https://www.fda.gov/media/188843/download?attachment
President Trump, Secretary Kennedy Announce Bold Actions to Tackle Autism Epidemic, US Department of Health and Human Services, 22 September 2025, https://www.hhs.gov/press-room/hhs-trump-kennedy-autism-initiatives-leucovorin-tylenol-research-2025.html
WHO statement on autism-related issues, World Health Organization, 24 September 2025
Dr. Oz Splits from Trump on Tylenol after Autism Tirade, the daily beast, 24 September 2025, https://www.thedailybeast.com/dr-oz-splits-from-trump-on-tylenol-after-autism-tirade/