Acetaminophen Use & Autism: You May Think Twice

Acetaminophen, commonly known as Tylenol®, is a medication used to treat fever and mild to moderate pain. Dr. Shaw owner of Great Plains Labs wrote about this topic in his newsletter stating there is strong evidence that increased acetaminophen use in genetically vulnerable children appears to be the major cause of the autism epidemic. Of course this possible genetic susceptibility is also a concern with pregnant women ingesting acetaminophen. Most pregnant women are told acetaminophen is an option to relive headaches with little known side effects. There are studies showing links to acetaminophen use in pregnancy and asthma in children but new research is adding autism to the list.

The toxicity of acetaminophen appears to cause autism in multiple ways according to this study. First, the genetic link is found on the cytochrome p450 2E1 system responsible for oxidative metabolism. Oxidative stress occurs when oxidants exceed the anti-oxidant defense and is higher in children with autism.

Second, toxicity of acetaminophen decreases sulfation pathways, which interfere with the body’s elimination of acetaminophen. The lack of elimination leads to intestinal Clostridia bacteria, which is commonly found in children with autism. The presence of Clostridia leads to a decrease in neurotransmitters and abnormal levels of neurotransmitters lead to symptoms of OCD, compulsive and stereotypical behaviors. So you can see this is a long messy chain.

When sulfation is diminished a larger than normal amount of acetaminophen is detoxified by the cytochrome p450 system and this leads to excessive production of a very toxic metabolite called N-acytl-p-benzoquinone imine (NAPQI) that depletes glutathione. Glutathione is a very important amino acid responsible for detoxification. If the body is low in glutathione it cannot process out this excessive amount of build up. The excessive NAPQI also leads to free radical and mitochondrial damage. When measured NAPQI levels were higher in people with decreased sulfation capacity.

It is very well known that children with autism lack proper detoxification pathways, mitochondrial damage, abnormal neurotransmitter levels, low glutathione and oxidative stress that contribute to the symptoms and delays we see clinically. I think it is best to avoid the use of acetaminophen in children on the spectrum and in pregnancy unless you have completed testing to rule out the genetic susceptibility. There are genetic tests out there that can tell you more about the susceptibility of your child.

As an alternative to acetaminophen I always suggest a few things that may help with a fever and body aches.