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. Tylenol's Impact on Glutathione and Liver Damage Acetaminophen, a Therapeutic or an Extremely Toxic RemedyA Review Researchers are studying a possible link between acetaminophen (Tylenol) use during pregnancy and higher autism or ADHD risk. It may lower glutathione, an important antioxidant for brain development. Electrochemical evidences in oxidation of acetaminophen in the presence of glutathione and N acetylcysteine Chemical Communications (RSC Publishing)