What is the primary use of N-acetylcysteine in clinical practice?

N-acetylcysteine is primarily used in clinical practice for managing acetaminophen intoxication. It acts as a mucolytic agent, but its most significant role is as an antidote for acetaminophen overdose. When acetaminophen is ingested in toxic amounts, it leads to the depletion of glutathione in the liver, resulting in hepatotoxicity due to the accumulation of toxic metabolites. N-acetylcysteine replenishes glutathione stores and helps to detoxify these harmful metabolites, thereby preventing or mitigating liver damage.

The timely administration of N-acetylcysteine in cases of acetaminophen overdose is crucial. If given within 8 to 10 hours of ingestion, it is highly effective in preventing liver failure, making it a cornerstone of treatment for this type of overdose. Its other applications, such as its use as a mucolytic agent to help reduce the viscosity of mucus in respiratory conditions, are secondary to its critical role in acetaminophen toxicity management.