On March 5, 2026, a study was published in the Lancet that revealed a concerning trend following a false claim made by former President Donald Trump. In September 2025, Trump falsely linked acetaminophen, the active ingredient in Tylenol, to an increased risk of autism. He recommended that pregnant women limit their use of the over-the-counter pain reliever, despite evidence to the contrary. Additionally, Trump and Secretary of Health and Human Services Robert F. Kennedy, Jr. recommended the use of leucovorin (folinic acid) for the treatment of autism, again without evidence to support their claims.
The study found that after Trump’s announcement, the number of pregnant patients in emergency rooms who took acetaminophen decreased by up to 20 percent. This decrease was not observed in nonpregnant patients. Furthermore, the study noted a 71 percent increase in the number of children aged five to 17 who were prescribed leucovorin as outpatients.
The impact of Trump’s false claims was significant, with thousands of women potentially forgoing necessary pain and fever relief during pregnancy. It is essential to note that acetaminophen is considered the safest pain reliever and fever reducer for use during pregnancy. Untreated fever during pregnancy can pose serious risks to the fetus, including miscarriage, birth defects, and premature birth.
Studies have shown no evidence of a link between acetaminophen use during pregnancy and an increased risk of autism or attention deficit hyperactivity disorder (ADHD) in children. In fact, fevers during pregnancy have been associated with a higher likelihood of autism in offspring. The Lancet study did not specify whether pregnant patients received alternative medications or went without treatment following the decrease in acetaminophen orders.
Regarding leucovorin, the medication promoted by Trump and his administration for autism treatment, studies supporting its effectiveness are considered provisional at best. The largest study on leucovorin included only 77 children and was retracted due to data analysis errors.
Overall, the study underscores the importance of evidence-based healthcare recommendations and the potential consequences of misinformation spread by public figures. Patients and healthcare providers rely on accurate guidance from governmental institutions to make informed decisions about their health. It is crucial to prioritize science-based information to ensure the well-being of patients and the integrity of medical practice.
