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. How NSAIDs Affect Glutathione Levels Pure TheraPro Rx Acetaminophen Toxicity: How Genetic Susceptibility Combines with Environmental Factors Tylenol, Autism, And The Glutathione Connection OC Integrative Medicine Current Insights into Glutathione Depletion in Adult Septic Patients Ibuprofen administration attenuates serum TNF levels, hepatic glutathione depletion, hepatic apoptosis and mouse mortality after Fas stimulation ScienceDirect