US President Donald Trump’s 2025 announcement linking autism to paracetamol use during pregnancy and endorsing leucovorin treatment may have been widely discredited in the months that followed, but it sparked millions of additional internet searches for the drugs and related products, a study has found.
The findings raise concerns about the influence of high-profile health messaging on patient behaviour, according to the authors of a research letter published in JAMA Network Open.
“Health leaders could consider how endorsements and warnings about medical products based on limited evidence may influence patients’ health decisions, and health care professionals could consider the influence of high-profile announcements on consumer health behaviour when counselling patients,” they wrote.
Researchers analysed Google search activity before and after the September 2025 press conference at which Mr Trump and senior health officials promoted leucovorin, a generic folinic acid formulation, for autism treatment and raised concerns about paracetamol exposure during pregnancy.
The claims prompted worldwide concern among clinicians and researchers, who questioned the strength of the evidence underpinning the statements.
Scientific reviews came out debunking the paracetamol-autism claims and saying it was too early to make a clear call on leucovorin.
Published in JAMA Network Open, the study used Google Trends data to compare observed search volumes during the two weeks after the announcement with forecasted search activity based on pre-announcement trends.
Searches for leucovorin were 378.7% higher than expected, equating to an estimated 1.19 million additional searches. Searches for folinic acid or folate rose 53.2%, generating a further 561,456 searches above expected levels.
By contrast, searches for multivitamins, used as a control, remained unchanged.
The researchers also found a substantial rise in searches suggesting consumers were looking to purchase the products.
Related
Searches indicating buying interest in leucovorin, folinic acid, or folate increased by 202.7%, representing an estimated 80,872 additional searches during the study period. Purchasing-related searches for multivitamins did not change.
Paracetamol (known as acetaminophen in the US) generated an even larger response.
Searches for the drug increased by 186.8%, amounting to almost 11.7 million additional searches above expected levels. Searches combining paracetamol with autism and/or pregnancy increased by 1322.4%, generating an estimated 4.37 million additional searches.
The study found a smaller increase in searches for ibuprofen, both generally and in connection with autism or pregnancy.
The researchers said this may reflect consumers seeking alternative pain-relief options or confusion about different medications. Searches for diphenhydramine, another control medication, remained stable.
They said the findings demonstrated how significantly high-profile political statements could influence public interest in health products and potentially affect healthcare decisions.
While the study did not assess whether online searches translated into actual medicine use, the researchers cited separate research showing decreased paracetamol use among pregnant women and increased leucovorin prescribing for children in the weeks following the announcement.
