Acetylcysteine (brand names – Acetadote, Mucomyst) is a cysteine (which is an amino acid) derivative that has beneficial effects on cocaine addiction in humans. It is believed to work via modulating glutamate release in the brain, due to the fact it is metabolised into cystine, which drives the cystine-glutamate antiporter in the brain. It is traditionally used to treat paracetamol overdose, due to its ability to readily metabolise into glutathione, the body’s chief antioxidant scavenger. Paracetamol-induced hepatotoxicity is mostly due to oxidative stress incurred by a toxic metabolite of paracetamol. Acetylcysteine is also used to treat chest congestion and has recently shown some ability to improve symptoms in those with psychiatric disorders.