Composition
- Each Tablet Contains:
- N Acetyl Cysteine
600 mg
Packing
- (1X10)
(Box)
MRP
- 320
Overview
Acetylcysteine is also known as N-acetylcysteine or N-acetyl-L-cysteine or NAC is primarily used as a mucolytic agent and in the management of acetaminophen poisoning. It is a derivative of cysteine with an acetyl group attached to the amino group of cysteine. NAC is essentially a prodrug that is converted to cysteine in the intestine by the enzyme aminoacylase 1 and absorbed in the intestine into the blood stream. Cysteine is a key constituent to glutathione and hence administration of acetylcysteine replenishes glutathione stores. It can also be used as a general antioxidant which can help mitigate symptoms for a variety of diseases exacerbated by reactive oxygen species .
Acetylcysteine is commonly used in individuals with renal impairment to prevent the precipitation of acute renal failure. Acetylcysteine treats mild to moderate traumatic brain injury including ischemic brain injury, particularly in reducing neuronal losses, and also reducing cognitive and neurological symptoms when administered promptly after injury. N-acetylcysteine is now widely used in the treatment of HIV, and it has reported efficacy in chronic obstructive pulmonary disease and contrast-induced nephropathy.
Indications
Acetylcysteine is used mainly as a mucolytic and in the management of paracetamol (acetaminophen) overdose.
PHARMACOLOGY
Mechanism of action:
Acetylcysteine protects against acetaminophen overdose-induced hepatotoxicity by maintaining or restoring hepatic concentrations of glutathione. It does this by producing the glutathione precursor L-cysteine. Glutathione is required to inactivate an intermediate metabolite (N-acetyl-p-benzoquinoneimine or NAPQI) of acetaminophen that is thought to be hepatotoxic. In acetaminophen overdose cases, excessive quantities of this metabolite are formed because the primary metabolic pathways become saturated. Acetylcysteine may act by reducing the metabolite to the parent compound or by providing sulfhydryl for conjugation of the metabolite. The mechanisms of action for acetylcysteine’s well-known mucolytic effects are different. when inhaled, acetylcysteine exerts its mucolytic action through its free sulfhydryl group, which reduces the disulfide bonds in the mucus matrix and lowers mucus viscosity. This action increases with increasing pH and is most significant at pH 7 to 9. L-cysteine also serves as a precursor to cystine which in turn serves as a substrate for the cystine-glutamate antiporter on astrocytes hence increasing glutamate release into the extracellular space. These effects on glutamate and NMDA signaling appear to explain some of the positive neuropsychotropic effects associated with NAC. Acetylcysteine also possesses some anti-inflammatory effects.
Pharmacodynamics:
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. It 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.
Pharmacokinetics:
Absorption: Bioavailability is 6–10% following oral administration and less than 3% following topical administration.
Metabolism: Hepatic. Deacetylated by the liver to cysteine and subsequently metabolized.Acetylcysteine is extensively liver metabolized,
Elimination:CYP450 minimal, urine excretion is 22-30% with a half-life of 5.6 hours in adults and 11 hours in neonates.
Side Effects
rash, urticaria,
itchiness
nausea, vomiting
stomatitis, fever
rhinorrhea, drowsiness
Clamminess
chest tightness
bronchoconstriction
Contraindication
Contraindications to its use include