Stacytine Mechanism of Action

Pharmacotherapeutic group: Mucolytics. ATC code: R05C B01.
Pharmacology: Pharmacodynamics: Acetylcysteine belongs to the group of amino acid cysteine derivative.
Mechanism of action: Acetylcysteine is believed to break the disulfide bonds in mucoproteins and it depolymerizes DNA strands in purulent mucus.
Pharmacodynamics effects: 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 effervescent tablet in adolescent population. However, mild, moderate or severe adverse reactions have been reported with the use of IV acetylcysteine including adolescents' population.
Pharmacokinetics: Absorption and metabolism: Acetylcysteine is absorbed rapidly and almost completely after oral administration. It is metabolized in the liver into a pharmaceutically active metabolite cysteine, inactive diacetylcystine and cystine and into the other disulfides. Due to the high first pass effect, the bioavailability of orally administered acetylcysteine is very low (approximately 10%).
In human peak plasma levels of acetylcysteine are reached in approximately 1-3 hours after an oral dose. Plasma concentration of the active metabolite cysteine about 2 μmol/l and binding with proteins is about 50%.
No dosage adjustments are required in patients with impaired kidney or liver impairment.
Elimination: Acetylcysteine is excreted almost entirely as inactive metabolites (inorganic sulfates, diacetylcystine) through the renal route. The elimination half-life of the acetylcysteine is about 1 hour, which is primarily determined by the rapid biotransformation in the liver. In patients with liver dysfunction the elimination half-life of acetylcysteine increases to 8 hours.
Distribution: In a pharmacokinetic study, intravenously administered acetylcysteine in human showed a distribution volume of 0.47 l/kg; the plasma clearance is 0.11 l/h/kg.
The elimination half-life after oral administration is 6.25 hours.
In a study with rats it was shown that acetylcysteine crosses the placenta.
There is no information on whether acetylcysteine crosses the blood-brain barrier in humans. There are no data on whether acetylcysteine is excreted in breast milk.
Hepatic and renal impairment: There is evidence that clearance of acetylcysteine can be significantly reduced up to 90% in the subjects with end-stage renal disease. This could result in a marked increase in systemic exposure to acetylcysteine in the extreme case of patients with end-stage renal disease. It is not known to what extent the results can be extrapolated to the less severe forms of renal impairment that are more likely to be encountered during routine use of proposed product.
The elimination half-life of acetylcysteine was found to increase to eight hours in one study of patients with chronic liver disease. The total clearance of acetylcysteine was found to be significantly reduced following an intravenous dose of 600 mg over three minutes in nine subjects with hepatic cirrhosis.