Yes there is good evidence that acetaminophen (the active ingredient in Tylenol) can deplete glutathione under certain conditions. But whether that matters depends on dose, duration, and individual factors. Jenny McCarthy's Glutathione and Tylenol Claims: Medical Toxicologist Weighs In MedPage Today Can Tylenol (acetaminophen) deplete glutathione levels in the body? Frontiers Potential adverse actions of prenatal exposure of acetaminophen to offspring Sex differences in glutathione metabolism and acetaminophen toxicity