Generic
Acetylcysteine
15 brands available in the market
At a glance
Acetylcysteine is a mucolytic agent that thins thick mucus in the airways, making it easier to cough out. It is used in respiratory diseases like bronchitis, asthma, and COPD, and also as an antidote for paracetamol overdose.
Description
Acetylcysteine is a mucolytic agent that reduces the viscosity of secretions by splitting disulphide bonds in mucoproteins and provides antisecretory effects. It clears the airways and facilitates breathing. It also has antioxidant properties by reacting with free radicals and serving as a precursor to glutathione, an important intracellular and extracellular antioxidant. It is available in oral, inhalation, and injectable forms. In paracetamol overdose, it detoxifies the toxic intermediate metabolite to prevent liver damage.
Indications
Respiratory diseases (chronic bronchopulmonary diseases such as COPD, emphysema with bronchitis, chronic asthmatic bronchitis, bronchiectasis; acute bronchopulmonary diseases such as asthma, bronchitis, bronchopneumonia, tracheobronchitis, bronchiolitis, pulmonary complications of cystic fibrosis, surgery-related pulmonary complications), paracetamol overdose (antidote).
Therapeutic class
Cough Expectorants & Mucolytics, Antidote Preparations
Pharmacological class
Mucolytic Agent & Antioxidant
Pharmacology
Acetylcysteine reduces the viscosity of secretions by splitting disulphide bonds in mucoproteins and provides antisecretory effects. It has antioxidant properties by reacting with free radicals and serving as a precursor to glutathione. In paracetamol overdose, it detoxifies the toxic intermediate metabolite N-acetyl-p-benzoquinone imine (NAPQI) to prevent liver damage.
Mechanism of action
Acetylcysteine splits disulphide bonds in mucoproteins to reduce mucus viscosity, making it easier to cough out and clear the airways. In paracetamol overdose, it detoxifies NAPQI to prevent liver damage.
Dosage
Effervescent/Dispersible Tablet (Adults & children >6 years): 600 mg once daily (evening), 5-10 days (acute) or long-term (chronic).
Effervescent Granules:
- Adults & children >6 years: 200 mg 2-3 times/day OR 100 mg 2 sachets 2-3 times/day
- Children 2-6 years: 100 mg 2-4 times/day (age-dependent)
Nebuliser Solution:
- Adults: 5-10 mL of 10% or 20% solution every 6-8 hours
- Infants 1-11 months: 1-2 mL of 20% or 2-4 mL of 10% solution every 6-8 hours
- Children 12 months-11 years: 3-5 mL of 20% or 6-10 mL of 10% solution every 6-8 hours
Paracetamol Overdose (Oral): Loading dose: 140 mg/kg, then maintenance: 70 mg/kg every 4 hours (total 17 doses).
Administration
Oral: Dissolve tablet/granules in a small amount of water and drink immediately. Effervescent tablet: dissolve in half a glass of water.
Nebuliser: Use 10% or 20% solution via nebuliser. May be diluted with recommended solutions.
Diagnostic Bronchograms: 1-2 mL of 20% or 2-4 mL of 10% solution 2-3 times by nebulisation or intratracheal instillation.
Missed dose
If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not double the dose.
Side effects
Common side effects: Headache, nausea, vomiting, abdominal pain, diarrhea, fever, rash, stomatitis, pruritus, urticaria, tachycardia, hypotension, tinnitus.
Serious side effects (rare): Anaphylactic shock, severe skin reactions, dyspnea, bronchospasm (especially in asthma patients).
Precautions & warnings
Bronchial asthma: Strict monitoring required during therapy; discontinue if bronchospasm occurs.
Peptic ulcer: Caution in patients with history.
Sodium-controlled diet: Each dose contains sodium (156.9 mg).
Pregnancy & lactation: Use under medical advice.
Sulfurous odor: Characteristic of the drug, not a sign of deterioration.
Contraindications
Hypersensitivity to acetylcysteine. Phenylketonuria (contains aspartame).
Drug interactions
Antibiotics (ampicillin, tetracycline, macrolides, cephalosporins, aminoglycosides, amphotericin): Acetylcysteine may reduce efficacy; maintain 2-hour gap.
Nitroglycerin: Acetylcysteine may enhance vasodilatory and antiplatelet effects.
Amoxicillin: May increase antibiotic levels in tissues.
Food interactions
Consuming alcohol does not cause any harmful side effects.
Use in pregnancy
Generally considered safe during pregnancy (Pregnancy Category: B). Animal studies have shown low or no adverse effects on the fetus; human studies are limited.
Pregnancy Category: B — always consult a doctor before taking during pregnancy.
Use in lactation
Probably safe during breastfeeding; limited data suggests no significant risk to the baby.
Pediatric use
Under 2 years: Oral: 200 mg once daily (effervescent granules).
2-6 years: 100 mg 2-4 times/day (effervescent granules).
>6 years: 600 mg once daily (effervescent tablet).
Nebuliser: Age and weight-based dosing (see above).
Geriatric use
No dose adjustment needed for elderly patients; however, caution is advised.
Renal / hepatic impairment
Renal impairment: No dose adjustment needed (limited data).
Hepatic impairment: No dose adjustment needed (limited data).
Overdose effects
Overdose symptoms: nausea, vomiting, diarrhea.
Storage conditions
Store in a cool and dry place, protected from light.
Chemical structure
C₅H₉NO₃S