A 48 hour fast can turn standard Paracetamol into acute liver failure. Fasting depletes Glutathione, leaving the liver defenseless against toxic NAPQI. Review the latest guidelines on BMJ Best Practice: https: bestpractice.bmj.com topics en us 1010 Acetaminophen or Tylenol Toxicity Lect 19 Pharmacology Paracetamol toxicity Deranged Physiology A study published in Gastroenterology describes a new mitochondrial mediator in the hepatotoxicity induced by paracetamol. Institute of Biomedical Research of Barcelona Myth busting, Acetaminophen version. "Avoid Acetaminophen (Tylenol) because it causes glutathione depletion". Truth?? As a pediatrician and ER doctor and as moms we're often asked about this. And we understand why: