Benefits of N-acetyl L-cysteine

Inhaled NAC is used for mucolytic therapy. It is used to dissolve the mucus formed in the throat and lungs. It acts as an adjuvant in respiratory conditions such as bronchitis, tuberculosis, pneumonia and emphysema. Benefits of N-acetylcysteine in the treatment of cystic fibrosis are still being researched upon.

Intravenous NAC is used to treat paracetamol overdose. Oral NAC is not preferred as many people have adverse reactions such as vomiting, nausea due to its unpleasant taste and odor. It also needs to be given in high doses due to poor oral bioavailability. Some people have been seen to show an allergic reaction even to the intravenous injection of NAC The symptoms include breathing difficulty, light-headedness, rashes and severe coughing. Another important benefit of N-acetylcysteine is its protective effects on the liver preventing liver disorders which may occur due to drugs and other toxic substances.

NAC also acts to replenish the antioxidant glutathione which is depleted during paracetamol overdose, in the body as it is its precursor. Together with glutathione it acts to metabolize the toxic substances by binding to it. Lack of glutathione contributes to adult respiratory stress syndrome and idiopathic pulmonary fibrosis. Glutathione is an antioxidant and it scavenges free radicals in the cell which can cause damage to the cell.

Oral NAC is used for the prevention of radiocontrast-induced nephropathy (which is a form of acute renal failure) and other renal disorders. N-acetylcysteine been shown to have beneficial effects on other conditions such as AIDS, cancer, heart disease and cigarette smoking. It also has a vasodialatory effect as it increases Nitric Oxide (NO) levels thereby increasing blood flow to the tissues.

N-acetylcysteine can cleave disulphide bonds present in proteins and convert them into sulfhydryl groups. This causes the mucoproteins (proteins that form a part of the mucus) in the lungs to break up and reduces congestion. It is therefore frequently used in the treatment of respiratory disorders.