N-Acetyl-L-cysteine is an acetylated amino acid with antioxidant and mucolytic properties. These two activities have made N-Acetyl-L-cysteine particularly relevant in cystic fibrosis studies, where the antioxidant/reducing character of the compound is described to ameliorate the characteristic systemic redox imbalance state of cystic fibrosis and the mucolytic properties of the compound are shown to impede upon the congestion and inflammation correlated to this redox state. As a mucolytic, N-Acetyl-L-cysteine serves to dissipate disulfide bonds across mucoproteins, loosening and clearing the viscosity of sputum. N-Acetyl-L-cysteine shows complimentary action to glutathione, both demonstrating antioxidant activity throμgh their thiol functionality, and both are shown to protect against peroxidative stress related to septic shock. N-Acetyl-L-cysteine has also been shown to induce apoptosis in vascular smooth muscle cells, indicating that these cells respond differently to changes in reduction-oxidation state than other tissues that are normally protected by the presence of antioxidants. This observation in vascular smooth muscle cells indicates N-Acetyl-L-cysteine as an interventional tool upon arteriosclerotic proliferation of these cells.An antioxidant mucolytic acetylated amino acid. N-Acetyl-L-cysteine is an acetylated amino acid with antioxidant and mucolytic properties. These two activities have made N-Acetyl-L-cysteine particularly relevant in cystic fibrosis studies, where the antioxidant/reducing character of the compound is described to ameliorate the characteristic systemic redox imbalance state of cystic fibrosis and the mucolytic properties of the compound are shown to impede upon the congestion and inflammation correlated to this redox state. As a mucolytic, N-Acetyl-L-cysteine serves to dissipate disulfide bonds across mucoproteins, loosening and clearing the viscosity of sputum. N-Acetyl-L-cysteine shows complimentary action to glutathione, both demonstrating antioxidant activity through their thiol functionality, and both are shown to protect against peroxidative stress related to septic shock. N-Acetyl-L-cysteine has also been shown to induce apoptosis in vascular smooth muscle cells, indicating that these cells respond differently to changes in reduction-oxidation state than other tissues that are normally protected by the presence of antioxidants. This observation in vascular smooth muscle cells indicates N-Acetyl-L-cysteine as an interventional tool upon arteriosclerotic proliferation of these cells. An antioxidant mucolytic acetylated amino acid.