Mucolus Mechanism of Action

Pharmacology: Pharmacodynamics: The effect of this activity is a reduction in the viscosity of mucous secretions. Another possible effect is detoxification of free radicals by interaction with the active sulfhydryl group of acetylcysteine.
In addition acetylcysteine increases synthesis of glutathione. Due to this mechanism of action, acetylcysteine is also indicated as a specific antidote in paracetamol poisoning.
There are no studies on the efficacy and safety of once daily acetylcysteine 600 mg capsules in the adolescent population. However mild, moderate or severe adverse reactions have been reported with the use of IV acetylcysteine including the adolescent population.
Pharmacokinetics: Acetylcysteine is rapidly absorbed from the gastrointestinal tract and peak plasma concentrations occur about 0.5 to 1 hour after oral doses of 200 to 600 mg. Some studies indicate dose-dependent pharmacokinetics with peak concentrations, the time taken to reach peak concentration and bioavailability increasing with increasing doses.
Acetylcysteine may be present in plasma as the parent compound or as various oxidized metabolites such as N-acetylcysteine, N, N-diacetylcysteine and cysteine either free or bound to plasma proteins by labile disulfide bonds or as a fraction incorporated into protein peptide chains.
In a study about 50% acetylcysteine was in a covalently protein-bound form 4 hours after a dose. Oral bioavailability is low and mean values have ranged from 4 to 10% depending on whether total acetylcysteine or just the reduced forms are measured. It has been suggested that acetylcysteine’s low oral bioavailability may be due to metabolism in the gut wall and first-pass metabolism in the liver. Renal clearance may account for about 30% of total body clearance. On intravenous dosage mean terminal half-lives have been calculated to be 1.95 and 5.58 hours for reduced and total acetylcysteine, respectively; the terminal half-life of total acetylcysteine was 6.25 hours after oral doses.
In other studies, it was observed that only three percent of radioactively-labeled acetylcysteine was excreted in the feces following oral administration which indicates almost complete absorption of acetylcysteine and its metabolites in the body.