N-acetylcysteine in clinical practice – properties, use and adverse effects

Abstract

N-acetylcysteine is a simple chemical compound with antioxidant and mucolytic properties. Currently, it is the primary treatment for acetaminophen poisoning. Prior to the introduction of acetylcysteine, acetaminophen overdose was associated with high mortality due to acute liver failure. Owing to its antioxidant properties, acetylcysteine maintains appropriate levels of glutathione, thereby protecting the liver from damage by toxic metabolites of paracetamol. Acetylcysteine is also used for infections with excess respiratory secretions. The mechanism of action of cysteine derivatives involves cleavage of disulfide bonds between the macromolecules present in the mucus and, consequently, reduction of mucus viscosity. Clinical trials have shown that N-acetylcysteine also plays an important role in relieving cough by eliminating mucus from the airways. Owing to its antioxidant properties, it can also prevent contrast-induced nephropathy. It was shown that prophylactic doses of acetylcysteine administered the day before and at the day of contrast administration are effective in preventing contrastinduced nephropathy in patients with chronic kidney disease. The compound can also modulate pathophysiological processes involved in many mental and neurological disorders. There is also evidence supporting the efficacy of acetylcysteine in mental disorders such as autism, schizophrenia, Alzheimer’s disease, psychoactive substance dependence or bipolar disorder. However, in addition to its therapeutic activity, the drug may also induce adverse effects. Adverse effects of varying severity have been reported since the introduction of acetylcysteine into clinical use.