Tylenol lowers glutathione, which is why it can cause liver failure. Low glutathione can cause many serious health problems that can vary from person to person. Finding out if you have genes that can Tylenol: How much is too much of a good thing? Allied Medical Training Is Tylenol Safe During Pregnancy? Understanding Risk Factors Seeking Health Early life acetaminophen exposure, glutathione S transferase genes, and development of adolescent asthma in a high risk birth cohort Journal of Allergy and Clinical Immunology Serotonin Deficiency Exacerbates Acetaminophen Induced Liver Toxicity In Mice Scientific Reports Acetaminophen Toxicity: How Genetic Susceptibility Combines with Environmental Factors