Drug Groups

approved

Description

Acetylcysteine is the N-acetyl derivative of cysteine. It is used as a mucolytic agent to reduce the viscosity of mucous secretions. It has also been shown to have antiviral effects in patients with HIV due to inhibition of viral stimulation by reactive oxygen intermediates. [PubChem]

Indication

Acetylcysteine is used mainly as a mucolytic and in the management of paracetamol (acetaminophen) overdose.

Pharmacology

Acetylcysteine has been shown to reduce the extent of liver injury following acetaminophen overdose. It is most effective when given early, with benefit seen principally in patients treated within 8-10 hours of the overdose. Acetylcysteine likely protects the liver by maintaining or restoring the glutathione levels, or by acting as an alternate substrate for conjugation with, and thus detoxification of, the reactive metabolite.

Toxicity

Single intravenous doses of acetylcysteine at 1000 mg/kg in mice, 2445 mg/kg in rats, 1500 mg/kg in guinea pigs, 1200 mg/kg in rabbits and 500 mg/kg in dogs were lethal. Symptoms of acute toxicity were ataxia, hypoactivity, labored respiration, cyanosis, loss of righting reflex and convulsions.

Affected Organisms

Biotransformation

Hepatic. Deacetylated by the liver to cysteine and subsequently metabolized.

Absorption

Bioavailability is 6–10% following oral administration and less than 3% following topical administration.

Half Life

5.6 hours (adults), 11 hours (neonates)

Protein Binding

83%

References

External Links