New research claims use of acetaminophen / paracetamol correlates with Autism and ADHD diagnosis rise

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Correlation with common over the counter acetaminophen and the rise of autism

Revolutionary new research published in the Journal of Evolutionary Medicine claims to have found a correlation in the rise of Autism and ADHD and asthma diagnosis with use of  acetaminophen, the main  component of painkiller Paracetamol in genetically or metabolically susceptible children, and the use of acetaminophen by pregnant women.

The in-depth research conducted by Dr William Shaw PhD looks at the build up of toxicity of acetaminophen and it’s effect on development of a specific enzyme which is deficient in autistic people and is responsible for catalysing desulfation pathways in the brain. Acetaminophen is sold in the US under many brand names but the most common is Tylenol® and is known as paracetamol in Europe being sold under the brand name of Panadol.

Low levels of this catalyst lead to over production of the toxic by-product of the pathway, namely the chemical N-acetylp- benzoquinone imine (NAPQI). A small amount of this chemical is usually broken down by the liver, but large amounts (as in paracetamol overdose) causes permanent liver damage.

The study shows that an increase in NAPQI also leaves an individual vulnerable to attack from the environment, so Dr Shaw asks the question could common advice as giving a child paracetamol before vaccination leave them susceptible to damage in the form of autism, asthma or ADHD?

The study compares USA and Cuba. In Cuba, children have a 99.7pc vaccination rate but are rarely given paracetamol. Autism prevalence in Cuba is 298 times lower in Cuba than in the USA.

Dr Shaw writes:

“In the United States, some physicians have started to advise parents to begin to take acetaminophen prophylactically daily 5 days prior to childhood vaccines; some children on such prophylactic treatment had an autistic regression that began prior to vaccination (personal communication, Kerry Scott Lane MD, Anesthesiologist, West Palm Beach, Florida, USA). In Cuba, acetaminophen is not approved as an over-the-counter (OTC) product, however, it has been available as an OTC product since 1959 in the United States. Furthermore, in Cuba, prophylactic use of antipyretic drugs is not the standard medical treatment for vaccine-related fever (personal communications with Dr Olympio Rodriquez Santos). If high fever continues after vaccination in Cuba for more than 2 days, the parents are advised to visit the physician’s office where the drug metamizole is most commonly prescribed. Prescription of acetaminophen in such cases is rare. Metamizole is used in many countries throughout the world but is banned in the United States and some other countries because of a rare association with agranulocytosis”

Paracetamol overtook Asprin as the painkiller of choice in the USA after a link was discovered between aspirn and Rye’s disease in the 1980’s.


The rise in autism, ADHD and asthma diagnosis seems to correlate directly with the use of paracetamol in the mainstream US population. The population of Cuba remained unaffected as paracetamol remained a prescription only drug in that country.

The researchers also looked at the effect of the drug on rat brains and more importantly a specific type of cell called Pyrkinje cells which are the largest neurons in the brain. These cells in people with autism are markedly different and behave differently. The study explains:

” In the brains of autistic patients, the most prominent histological changes were observed in the cerebellum, characterized by a patchy loss of neurons in the Purkinje cell layer and granular cell layer in nine out of ten cerebella; one of these cerebella also showed an almost complete loss of Purkinje cells from the Purkinje cell layer, as well as a marked loss of granular cells. Kern and Jones have summarized the important role of Purkinje cell abnormalities in autism, especially the susceptibility of these cells to oxidative stress during GSH depletion.”

It continues with evidence:

It would seem likely that perhaps some children on the autistic spectrum might have both brain and lung abnormalities caused by acetaminophen. Is there any evidence for such combined abnormalities? Indeed, at the annual meeting of the American College of Chest Physicians in Honolulu, Hawaii in 2011, Barbara Stewart, a paediatric pulmonologist, found that a significant lung abnormality was present in 100% of children (n = 47) on the autistic spectrum who were examined, but in none of <300 children without autism.68 Most of the children with autism had been referred to her clinic due to persistent cough unresponsive to treatment. She noticed during bronchoscopy examinations, in which a lighted tube is inserted into the lungs, that, although the airways of the children initially appeared normal, the lower airway had doubled branches, or “doublets”.

Dr. Stewart said “when airways divide beyond the first generation, they typically branch like a tree, with one branch on one side and one on the other. A doublet occurs when there are twin branches that come off together instead of one, which are exactly symmetrical, in each of the lower locations that can be seen.”

In a study of ASD children in Sweden, airway symptoms of wheezing and physician-diagnosed asthma in the baseline investigation in infants and toddlers were associated with ASD 5 years later .It would seem very useful to examine the use of acetaminophen both prenatally and post-natally in the children with the abnormal lung anatomy.”