![\"Tylenol](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/09\/d41586-025-03116-2_51477694.jpg\"\/)
<\/p>\n <\/p>\n
Tylenol has been used to treat common pains and fevers since 1893. Why is it still among the most commonly taken painkillers?Credit: Valerie Macon\/AFP via Getty<\/p>\n
Tylenol \u2014 also known as paracetamol, or acetaminophen \u2014 has been a common household medicine for decades, but has rarely received as much attention as this week when Donald Trump linked it to autism<\/a>.<\/p>\n Trump links autism and Tylenol: is there any truth to it?<\/p>\n <\/a><\/p>\n The claim was swiftly discredited by several researchers, who pointed out that the most robust and largest studies testing the possible impact of pregnant women taking the drug find no evidence of any connection to autism in children. Outside the United States, paracetamol is still recommended<\/a> as a first-line treatment for pain and fever in pregnancy, and scientists say there have been no causal associations between the drug and neurodevelopmental disorders. Untreated pain and fever, on the other hand, can harm mothers and fetuses1<\/a>.<\/p>\n Paracetamol is one of the safest medicines available, with very few possible complications \u201cas long as you stick to the [recommended] doses\u201d, says Tony Dickenson, a neuroscientist at University College London. The drug is far more lethal in animals with different liver enzymes \u2014 such as snakes. That\u2019s why in 2013 the United States airdropped thousands of paracetamol-laden dead mice to control invasive populations of brown tree snakes on the Pacific Island of Guam. Here\u2019s what we do and don\u2019t know about the drug.<\/p>\n Mysterious mechanism<\/p>\n Despite decades of clinical use, and the proposal of several molecular mechanisms, researchers still don\u2019t fully know how paracetamol dulls pain.<\/p>\n Most research on paracetamol has been directed to what happens inside the brain, says Dickenson. \u201cParacetamol, apart from being an analgesic, is pretty good at reducing fevers,\u201d he says. That\u2019s controlled by the brain\u2019s hypothalamus. \u201cSo, the drug is clearly getting into the brain.\u201d<\/p>\n Autism is on the rise: what\u2019s really behind the increase?<\/p>\n <\/a><\/p>\n This action on the central nervous system \u2014 protected behind the blood\u2013brain barrier<\/a> \u2014 makes paracetamol different to other, anti-inflammatory painkillers such as ibuprofen and aspirin, which tend to work at the peripheral site of tissue damage. Studies also suggest the drug acts on neuronal pathways between the brain and the spinal cord that alter the gain of pain signalling2<\/a>. \u201cThere are multiple systems and all of those are critical for pain processing,\u201d says Dickenson. \u201cSo, it is pretty difficult to tease out what’s going on.\u201d<\/p>\n![\"\"](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/09\/d41586-025-03116-2_51473450.jpg\"\/)
<\/p>\n![\"\"](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/09\/d41586-025-03116-2_51426444.jpg\"\/)
<\/p>\n