Cysteine

Cysteine is a semiessential proteinogenic amino acid and a building block of proteins used throughout the body. It is commonly found as a component of total parenteral nutrition (TPN) to meet nutritional requirements in hospitalized patients and newborns requiring intravenous feeding[3][8]. Cysteine acts as an antioxidant due to its thiol group and serves as a precursor for glutathione synthesis—a key intracellular antioxidant[2][5]. In medicine (notably as N-acetylcysteine), it is used as an antidote for acetaminophen overdose by binding toxic metabolites in the liver[1][2][3]. It also has mucolytic properties and can help break down mucus in respiratory conditions. Cysteine may be essential under certain conditions such as infancy or metabolic disease[3].

Brand names

ElcysFreamine 6.9Freamine6.9Freamine-6.9Freamine III 10Hepatamine 8Hepatamine8Hepatamine-8NephramineNouressPremasolPrimeneProcalamine 3Procalamine3Procalamine-3Trophamine 10 %

Other names

L-cysteineAcetylcysteineN-acetylcysteineNAC