The US authorities has announced controversial guidance on the prevention and remedy of autism in youngsters.
New health recommendations purpose to discourage pregnant girls from taking the painkiller paracetamol—also referred to as acetaminophen and by the brand name Tylenol—to forestall autism.
The suggestions additionally embrace utilizing the drug leucovorin to deal with speech-related difficulties that youngsters with autism typically expertise.
So what’s leucovorin and what does the science say about its capability to deal with autism?
What’s leucovorin?
Leucovorin is a type of folic acid, a B vitamin our our bodies usually get from foods resembling legumes, citrus fruits, and fortified grains.
The medicine is most frequently utilized in most cancers remedy. It’s usually used alongside the chemotherapy drug fluorouracil, a most cancers remedy that stops most cancers cells from making DNA and dividing. Leucovorin enhances the results of fluorouracil.
Leucovorin can also be used to cut back the toxic side effects of methotrexate, one other chemotherapy drug.
Methotrexate works by blocking the physique’s use of folate, which wholesome cells have to make DNA. Leucovorin supplies an lively type of folate that wholesome cells can use to make DNA, thereby “rescuing” them whereas methotrexate continues to focus on most cancers cells.
As a result of methotrexate can also be used to deal with the pores and skin situation psoriasis, leucovorin will also be used as a rescue agent during treatment for this autoimmune situation.
Why is folate vital?
As a result of folate is important for making DNA and different genetic materials, which cells have to develop and restore correctly, it’s particularly vital throughout pregnancy.
It is because inadequate folate is linked to the event of spina bifida, a situation the place a child’s backbone doesn’t develop appropriately. For that reason, girls are suggested to take folic acid dietary supplements earlier than conception and through the early months of being pregnant.
Folate can also be vital for supporting the manufacturing of pink blood cells and overall brain function.
Why is it being thought of to deal with autism?
The advice to make use of leucovorin to deal with autism appears to stem from a idea that low ranges of folate within the mind can result in a situation referred to as cerebral folate deficiency.
Youngsters with cerebral folate deficiency don’t normally show signs for the primary two years. Then they present indicators of speech difficulties, seizures, and intellectual disability.
Because the indicators of autism are comparable and it normally presents at around the same age, some individuals have proposed a hyperlink between cerebral folate deficiency and autism.
What does the proof say?
So can giving youngsters folate, within the type of leucovorin, assist them to perform higher with autism? The proof says possibly sure, and right here’s what we all know to date.
A evaluation of the evidence in 2021 analysed the outcomes of 21 research that used leucovorin for autism or cerebral folate deficiency. Youngsters who took the drug typically had improved autism signs. However the authors additionally stated extra research have been wanted to substantiate the findings.
Since then, a small 2024 study concerned about 80 youngsters aged two to 10 years with autism. Half took a every day most dose of 50mg of folinic acid (just like leucovorin), the opposite half took a placebo. Youngsters given folinic acid confirmed extra pronounced enchancment compared with those that took the placebo.
An analogous 2025 study examined the identical dose of folinic acid given to Chinese language youngsters with autism. These given folinic acid had higher enchancment in a sort of social skill referred to as social reciprocity compared with youngsters given placebo.
Whereas promising, none of those trials are on the degree to alter medical apply. We’d want additional, bigger research earlier than docs could make a correct advice.
Like all medicine, leucovorin has side effects. Probably the most severe or frequent are extreme allergic reactions, seizures and matches, and nausea and vomiting.
In a nutshell
General, the most recent well being suggestions are usually not but backed by adequate proof.
Whereas the US Meals and Drug Administration will now allow doctors to prescribe leucovorin to deal with autism signs, the Australian authorities shouldn’t change its prescribing steering.
Assist for individuals with autism ought to proceed to observe evidence-based best practice till the info from scientific trials of leucovorin is extra strong.
Nial Wheate is a professor on the Faculty of Pure Sciences at Macquarie University and Jasmine Lee is a pharmacist and PhD candidate on the University of Sydney.
This text is republished from The Conversation below a Inventive Commons license. Learn the original article.

