Doctor using microscope
Chokniti Khongchum/Pexels

Folinic acid, also known as leucovorin, is drawing worldwide attention after United States health officials, including Dr Mehmet Oz, highlighted its potential benefits for some children with autism. The decades-old chemotherapy support drug is now being considered for wider use in treating cerebral folate deficiency linked to autism spectrum disorder (ASD), while online retailers such as iHerb and Amazon are fuelling consumer interest.

What is Folinic Acid?

Folinic acid, sold under the name leucovorin, is a biologically active form of folate that differs from standard folic acid. It has been used in oncology since the 1950s, particularly to reduce the toxic side effects of methotrexate in cancer patients. It is also prescribed for folate-deficiency anaemia and rare metabolic disorders.

Because leucovorin bypasses certain metabolic pathways, it can deliver folate to cells even when folate transport is impaired. This mechanism is central to its emerging role in autism research.

Why It Is Linked to Autism

Some children with ASD exhibit cerebral folate deficiency, a condition where folate cannot efficiently cross into the brain due to autoantibodies that block transport. Researchers believe leucovorin may overcome this barrier and improve neurological function.

Clinical studies have produced early but notable findings. Several small randomised controlled trials have reported gains in verbal communication and social interaction among children with autism who were given folinic acid. These improvements are particularly evident in those who test positive for folate receptor autoantibodies.

Federal Spotlight and Dr Oz's Role

According to an FDA News Release on 22 September 2025, US health officials plan to expand leucovorin's approved use to include children with cerebral folate deficiency and autism-like symptoms.

Dr Mehmet Oz, Administrator of the Centres for Medicare and Medicaid Services, took part in the announcement. His presence helped elevate the discussion from specialist medical circles into mainstream media headlines.

The policy discussions coincided with political interventions by figures including President Donald Trump and Health Secretary Robert F Kennedy Jr, who drew attention to broader debates around autism treatments. Their involvement has made leucovorin part of a heated national conversation.

Retail Boom on iHerb and Amazon

Interest in folinic acid is not confined to hospitals and clinical trials. Supplements containing folinic acid are widely available on retail platforms such as iHerb and Amazon. Brands like California Gold Nutrition and Seeking Health offer folinic acid in tablets and lozenges, often marketed as supporting cellular health and methylation.

Customer reviews on these platforms frequently mention autism, with parents reporting perceived improvements in their children's speech and behaviour. This online marketplace activity has driven consumer demand and contributed to folinic acid's growing visibility outside clinical environments.

Evidence and Expert Caution

Despite the enthusiasm, experts stress that leucovorin is not a cure for autism. While small trials suggest some children may benefit, the overall evidence remains limited and inconsistent. Larger, more rigorous studies are required to confirm both efficacy and safety across broader populations.

Medical professionals warn that benefits are likely restricted to children with specific biological markers, such as folate receptor autoantibodies. Unsupervised use of high-dose supplements can pose risks, and paediatric neurologists advise medical testing before beginning any folinic acid regimen.

Political and Public Debate

The heightened focus on leucovorin has unfolded in a politically charged atmosphere. During the same briefings, some political figures revived contested claims about links between acetaminophen and autism, drawing criticism from health experts who caution against misinformation.

Autism organisations and scientific bodies continue to urge families to rely on evidence-based guidance, emphasising that while leucovorin shows promise in targeted cases, widespread adoption should await stronger clinical proof.

Writer's pick