N-acetylcysteine (NAC) is the acetylated precursor of both the amino acid L-cysteine and reduced glutathione (GSH). Historically it has been used as a mucolytic agent in chronic respiratory illnesses as well as an antidote for hepatotoxicity due to acetaminophen overdose. More recently, animal and human studies of NAC have shown it to be a powerful antioxidant and a potential therapeutic agent in the treatment of cancer, heart disease, HIV infection, heavy metal toxicity, and other diseases characterized by free radical oxidant damage. NAC has also been shown to be of some value in treating Sjogren's syndrome, smoking cessation, influenza, hepatitis C, and myoclonus epilepsy.
N-乙酰半胱氨酸（NAC）是氨基酸L-半胱氨酸和还原型谷胱甘肽（GSH）的乙酰化前体。从历史上看，它一直被用作慢性呼吸道疾病的黏液溶解剂以及对乙酰氨基酚过量导致肝毒性的解毒剂。最近，对NAC的动物和人体研究表明，它是一种强大的抗氧化剂，也是治疗癌症、心脏病、HIV感染、重金属中毒以及其他以自由基氧化损伤为特征的疾病的潜在治疗剂。NAC在治疗干燥综合征、戒烟、流感、丙型肝炎和肌阵挛性癫痫方面也显示出一定价值。
