The recent surge in leucovorin prescriptions for children with autism spectrum disorder (ASD) following high-profile endorsements by President Donald Trump and Robert F. Kennedy Jr. has sparked both interest and skepticism. While some families have embraced the medication as a potential treatment, others remain cautious due to the limited evidence supporting its effectiveness. This article delves into the story behind the leucovorin trend, exploring the factors that drove its popularity and the ongoing debate surrounding its use.
The Trump Bump and RFK Jr.'s Influence
The story begins in September 2025 when Trump and RFK Jr. made a bold claim about acetaminophen (Tylenol) and its alleged link to autism. While this claim was widely disputed by experts, it inadvertently drew attention to leucovorin, which was also mentioned during the same press conference. The connection between leucovorin and autism was tenuous, based on limited studies suggesting low folate levels in children with ASD and the resemblance of cerebral folate deficiency symptoms to severe autism.
RFK Jr. and former FDA Commissioner Marty Makary made dramatic assertions about leucovorin's potential to benefit large numbers of children with autism. Makary's statements, in particular, were attention-grabbing, suggesting that leucovorin could help hundreds of thousands or even up to 50% of kids with autism. These endorsements, combined with the media coverage, likely played a significant role in the subsequent surge in leucovorin prescriptions.
A Spike in Prescriptions
Researchers at the University of California, San Diego, analyzed prescription trends of leucovorin among children with autism using the EPIC Cosmos database. They observed a clear bump in leucovorin prescriptions following the Fox News report in February 2025, which detailed success stories from families who believed the drug improved their children's speech deficits. This was followed by an even more significant spike after the Trump announcement in September.
The prescription rate of leucovorin skyrocketed from around 34 prescriptions per 100,000 outpatient visits in 2023 and 2024 to 835 prescriptions per 100,000 visits by November 2025. This represents a more than 2,000% increase in leucovorin prescriptions for children with ASD, according to the study's lead author, Joshua Rothman.
The FDA's Cautious Approval
Despite the surge in interest, the Trump administration's enthusiasm for leucovorin has cooled. In March 2026, the FDA approved the expanded use of leucovorin to treat cerebral folate deficiency but explicitly declined to endorse it as an autism treatment. The agency cited the lack of strong evidence to support such a decision, acknowledging the weak data supporting leucovorin's effectiveness for autism.
This cautious approach is supported by recent developments in research. A major trial testing leucovorin supplements in children with autism was retracted due to data errors and concerns. The retraction highlights the ongoing uncertainty surrounding leucovorin's role in treating autism.
The Need for Further Research
While the study by Rothman and his team does not evaluate leucovorin's usefulness for autism, it emphasizes the need for more research. With the increasing number of families prescribed leucovorin, there is a growing imperative to assess the long-term outcomes and share these results with the public.
Rothman argues that it is the responsibility of scientists and clinicians to generate rigorous data to inform families and clinicians about the potential benefits and risks of treatments like leucovorin. As the debate surrounding leucovorin's role in autism continues, further research is essential to provide clarity and guide clinical decision-making.
In conclusion, the story of leucovorin's rise and fall in the context of autism treatment highlights the complex interplay between public figures, media coverage, and scientific evidence. While the initial enthusiasm was high, the lack of strong data has led to a more cautious stance. The ongoing debate underscores the importance of rigorous research to ensure that families and healthcare providers have access to accurate information when making treatment choices for children with ASD.
