In 2025, the number of children receiving a drug promoted — but unproven — for autism treatment grew, especially toward the end of the year. A new study suggests the late rise was influenced by a Trump administration announcement.
At a White House briefing on September 22, 2025, President Trump touted the drug leucovorin as a potential therapeutic for autism. The week before the announcement, roughly 5 children per 100,000 received leucovorin via a prescription in the United States. The week of the announcement, the pharmacy dispensing rate climbed to roughly 7 children per 100,000. By the end of the year, the rate rose to 8 children per 100,000, researchers reported August 12 in the New England Journal of Medicine.
“Our study demonstrates the power of the federal government to influence clinical practice,” says Kao-Ping Chua, a pediatrician and health policy researcher at the University of Michigan Medical School in Ann Arbor. If administration communications and decisions are not based on rigorous scientific evidence, it could lead to harms “including giving people false hope and potentially exposing them to the side effects of ineffective medical treatments.”
Leucovorin is a form of the essential vitamin folic acid. The drug is prescribed when the body’s method for breaking down folic acid from food is impaired. The U.S. Food and Drug Administration had approved leucovorin for use with certain genetic disorders and to help reduce the side effects of chemotherapy drugs that disrupt that break down. The American Academy of Pediatrics does not recommend leucovorin for autism because of the lack of evidence surrounding dosing, effectiveness and safety.
Chua and colleagues analyzed a database that includes more than 90 percent of U.S. retail pharmacy prescriptions to study changes in leucovorin dispensing for children ages 0 to 17 years. More than 150,000 prescriptions were given to over 47,000 children from the end of 2024 to the end of 2025. The dispensing rate had been climbing but rose more sharply from the week of briefing to the end of the year, the team found. There wasn’t a similar trend in the dispensing rate for adults.
The new research adds to another group’s Lancet study, which analyzed a smaller dataset based on emergency departments and outpatient clinics, that found an increase in prescriptions for leucovorin following the briefing for children 5 to 17 years old.
In March 2026, the FDA approved leucovorin for a rare condition called cerebral folate deficiency. But contrary to the claims made at the White House briefing, FDA officials said there wasn’t enough evidence to support using the drug for autism.
There haven’t been large, randomized trials evaluating the efficacy or long-term safety of leucovorin for children with autism. With the rise in dispensing, Chua says, “the concern is that clinicians are increasingly prescribing an unproven drug with an unclear safety profile to children.”
