Evidence That Acetaminophen Triggers Autism in Susceptible Individuals Has Been Ignored and Mishandled for More than a Decade

Overwhelming evidence shows that exposure of susceptible babies and children to acetaminophen (paracetamol) triggers many if not most cases of autism spectrum disorder, and that oxidative stress causes susceptibility. However, these conclusions have not yet been widely acknowledged or integrated into clinical practice or regulatory guidelines, leaving the continued high prevalence of autism spectrum disorder unchecked. To understand why the conclusions have not been widely accepted, this study conducts systematic analyses of all PubMed-indexed papers with “acetaminophen” and “autism” in any search field. In these papers, statements that failed to promote changes in clinical practice or regulatory guidelines were pervasive. Also pervasive were mishandlings of available evidence, including treating interacting variables as if they are confounding factors (66% of studies affected) and considering too narrow a range of evidence (77% of studies affected). Also present were erroneous criticisms of potentially groundbreaking research, undermining the potential impact of that research. It is hoped that identification of these fundamental problems will lead to widespread acceptance of the evidence that acetaminophen triggers autism spectrum disorder in susceptible babies and children and to subsequent regulatory and clinical changes that will effectively and quickly reduce the induction of autism spectrum disorder.