President Donald Trump has announced that his administration is preparing to warn pregnant women that using Tylenol—scientific name acetaminophen—may be connected to an increased risk of autism in children. The proposal includes recommending that women avoid the drug during pregnancy unless it’s necessary, such as for treating a high fever.
Alongside this claim, the administration is promoting leucovorin, a drug usually used to treat folate deficiency, as a possible treatment for some symptoms of autism.
Medical experts and drug manufacturers have pushed back, saying there’s no strong scientific evidence proving acetaminophen causes autism. Many studies have explored an association, but none have definitively established causation. Researchers caution that more rigorous research—such as large controlled trials—is needed before changing health guidelines for widespread use.