While probably not harmful, there is not enough evidence that leucovorin is an effective treatment for autism. Demand for the drug among parents of children with autism recently skyrocketed after a press conference last fall in which federal health officials claimed, with little evidence, that the drug is a promising treatment for autism.
You may have heard of folic acid and folate. Both are forms of vitamin B9. Leucovorin, also called folinic acid, is a reduced form of folate. Folic acid and folate are found in foods and supplements and are essential for many functions in the body. The leucovorin being discussed for autism is a prescription medication that is mainly used in certain cancer treatment regimens and to treat rare deficiencies and toxicities. The current administration correctly stated that the drug could be used to treat cerebral folate deficiency (CFD), a rare brain disorder. CFD is marked by low folate levels in cerebrospinal fluid and usually appears in infancy, causing a variety of neurological symptoms, such as seizures and cognitive impairment. It may be present in a subset of autistic people, but the condition is so rare (only 50 cases ever documented in the medical literature) that it is very challenging to say what, if any, connection there is between CFD and autism.
So far, there’s no strong evidence that leucovorin is beneficial for children with autism who do not have CFD. Currently, there are only a few double-blinded, placebo-controlled trials (the gold standard for new treatments) that have tested the drug’s effectiveness in children with autism. The largest of them was retracted in early 2026 due to problems with the data and statistical analyses. Experts say there’s not enough research to know whether leucovorin can benefit kids with autism or how to safely prescribe it and monitor kids who are taking it.
This limited research is why the American Academy of Pediatrics, the Child Neurology Society, and the Society for Developmental and Behavioral Pediatrics are recommending against the routine use of leucovorin for autism.
Unfortunately, the current administration’s claim that leucovorin could help “tens of thousands” of children with autism has led to a lot of false hope. The increasing demand for the drug has created rifts between patients and doctors, many of whom are reluctant to prescribe it due to limited evidence. As pediatric neurologist Audrey C. Brumback wrote in an op‑ed for MedPage Today, “[Patients] deserve the best that science and medicine have to offer. That doesn’t include prescribing drugs without scientific evidence, which are unlikely to help and could even cause harm.”
Autism is a complex neurological condition and each child is unique. At present, parents often have more questions than experts have answers to. That’s especially frustrating when getting an appointment or even having time to ask questions can be difficult. Still, your child’s clinician is one of your best sources of information, and they can help you sort through options based on your child’s specific situation.
