N-Acetyl-Cysteine - N-Acetyl-Cysteine (N-A-C) is a modified form of the amino acid and antioxidant. NAC helps break down mucus and protects from acetaminophen toxicity. In addition, it helps the body to synthesize the antioxidant glutathione, which is produced intracellularly, primarily by the liver. Glutathione exerts a variety of protective effects, including detoxification and intracellular defense against oxidative stress. Substances known to reduce glutathione status are acetaminophen and alcohol. Buy N-acetyl cysteine Supplements on discount at HerbsMD.