A Year After Trump's Tylenol Warning, 3 Million-Patient Review Finds No Causal Autism or ADHD Link

A year after President Donald Trump told pregnant women "Don't take Tylenol", a major review has found that the available evidence does not support a robust causal link between the painkiller and autism or ADHD in children. The analysis drew on data from more than 3 million participants.

The umbrella review, published this week in Developmental Medicine & Child Neurology, combined the results of seven meta-analyses. It concluded that paracetamol, the drug sold as Tylenol in the US, 'remains an appropriate first-line treatment during pregnancy when clinically indicated.'

The findings arrive almost exactly 12 months after Trump and US health officials raised concerns about acetaminophen use during pregnancy. They add to the evidence available to expectant mothers who have faced uncertainty over whether they can safely treat a fever or persistent pain.

Autism and ADHD Signal Fades in Stronger Studies

When the available meta-analyses were included, the researchers did find a small statistical association. The risk ratios were 1.17 for autism and 1.29 for ADHD.

That signal weakened sharply once the analysis was limited to higher-quality meta-analyses and low-risk primary studies. The estimates then approached the null value, meaning the observed associations were substantially reduced.

'Our findings show that the apparent association between prenatal paracetamol exposure and autism or ADHD weakens as methodological quality improves, challenging the interpretation of a causal link...' first author Hoda Tayebi-Hillali, of the University of Santiago de Compostela in Spain, said in a statement.

The paper states that the associations reported in earlier research 'are probably influenced by methodological limitations.' In other words, differences in study design and other methodological issues may help explain the apparent link.

A Year After the White House Warning

Trump made his remarks alongside Health and Human Services Secretary Robert F. Kennedy Jr. On the same day, the US Food and Drug Administration said it was starting the process of changing acetaminophen labels to reflect a possible association with autism and ADHD, and it sent a letter to doctors across the country.

The agency's own announcement acknowledged that 'a causal relationship has not been established and there are contrary studies in the scientific literature.'

FDA Commissioner Marty Makary said in the same release that the change 'may lead many to avoid using acetaminophen during pregnancy, especially since most low-grade fevers don't require treatment.'

The new review reaches a different conclusion on whether the evidence supports changing prescribing recommendations. Its authors wrote that the available evidence 'does not support changes to existing prescribing recommendations when considering the balance of risks and benefits.'

What It Means for Pregnant Women

In the UK, the Medicines and Healthcare products Regulatory Agency issued a reminder to healthcare professionals on 23 September 2025 that paracetamol remains the first-choice pain reliever during pregnancy when clinically indicated.

The regulator also warned that patients should not switch to alternatives such as ibuprofen, which is generally not recommended during pregnancy. It advised that paracetamol should be used at the lowest dose and for the shortest duration necessary.

The authors of the new review raised a similar concern. They said any decision must take account of the potential consequences of untreated maternal fever, pain or inflammatory conditions.

Paracetamol remains one of the main pain and fever medicines used during pregnancy. The review therefore adds to an ongoing debate over how the drug's potential risks should be weighed against the consequences of untreated symptoms.

This is the latest of several large analyses, including a June study in JAMA Internal Medicine and a Danish nationwide study, to report no association between the drug and autism or ADHD in their analyses. The findings add to the evidence that US regulators will consider as the ongoing acetaminophen labelling process continues.