Acetylcysteine

Prescribing Information (Research Brand)

Indications

Acetylcysteine is indicated as an adjunctive treatment for patients with abnormal, viscid or inspissated mucus secretions associated with conditions such as-

Acute and chronic bronchopulmonary disorders (e.g. pneumonia, bronchitis, emphysema, tracheobronchitis, chronic asthmatic bronchitis, tuberculosis, bronchiectasis, primary amyloidosis of the lung) Atelectasis caused by mucus obstruction  Pulmonary complications of cystic fibrosis Pulmonary complications of thoracic and cardiovascular surgery  Post-traumatic chest conditions.

It is effective in all respiratory airways disease causing formation of a dense secretion that cannot be or can only partially be expectorated such as acute and chronic bronchitis, laryngitis, sinusitis, tracheitis, infuenza & bronchial asthma. Acetylcysteine is also indicated in the treatment of Paracetamol overdose. Treatment option is optimal if given within 8 hours of Paracetamol ingestion.

Therapeutic Class

Antidote preparations, Cough expectorants & mucolytics

Pharmacology

Acetylcysteine has a mucolytic activity through its free sulfhydryl group. It acts directly on the mucoproteins to open the disulfide bonds and thus lowers the viscosity of the mucous and facilitates its removal by the muco-cillary action and expectoration. Acetylcysteine improves the phagocytic capacity of the alveolar macrophages, thus protecting lungs from a variety of insults. Acetylcysteine is a precursor to glutathione, the most important intra & extra-cellular antioxidant (the safest & most convenient)

Dosage & Administration

Acetylcysteine Tablet:

The dispersible tablet should be dissolved in 1/2 glass of water before use (preferably in the evening). The duration of treatment should be 5 to 10 days in the acute phase. It may be continued in the chronic state for up to 6 months or according to the advice of the physician.

As a mucolytic:
  • Adults: 600 mg daily as a single dose.
  • In Paracetamol overdose: Initially 140 mg/kg, followed by 70 mg/kg every 4 hours for an additional 17 doses. As an antidote, Acetylcysteine is reported to be very effective when administered within 8 hours of Paracetamol overdose, with the protective effect diminishing after this time. Initiation of treatment after a lapse of 15 hours has previously been thought to be ineffective, but recent studies suggest that beneficial results may still be obtained.


Acetylcysteine Respirator Solution:

The 20% solution may be diluted to a lesser concentration with either Sodium Chloride for injection, Sodium Chloride for inhalation, sterile water for injection, or sterile water for inhalation.

As a mucolytic:
Adult:
  • 5-10 ml of 10% or 20% solution by nebulizer every 6-8 hr PRN.
Children:
  • 1-11 months: 1-2 ml of 20% or 2-4 ml of 10% solution by nebulizer every 6-8 hr PRN.
  • 12 months-11 years: 3-5 ml of 20% or 6-10 ml of 10% solution by nebulizer every 6-8 hr PRN.
  • Below 12 years: 5-10 ml of 10/20% solution by nebulizer every 6-8 hr PRN.
Diagnostic Bronchograms: 1-2 ml of 20% or 2-4 ml of 10% solution 2-3 times by nebulization or by instillation intratracheally prior to procedure.

Nebulization tent or croupette: This form of administration requires very large volumes of the solution, occasionally as much as 300 ml during a single treatment period. If a tent or croupette must be used, the recommended dose is the volume of acetylcysteine (using 20%) that will maintain a very heavy mist in the tent or croupette for the desired period. Administration for intermittent or continuous prolonged periods, including overnight, may be desirable.

Direct Instillation: When used by direct instillation, 1-2 ml of a 20% solution may be given as often as every hour. When used for the routine nursing care of patients with tracheostomy, 1-2 ml of a 20% solution may be given every 1-4 hours by instillation into the tracheostomy.

Interaction

After taking Acetylcysteine orally it increases the bioavailability of Amoxicillin, but shows no effect on Doxycycline and reduces the absorption of Cefalexin. Acetylcysteine seems to increase the effects of Nitroglycerin.

Contraindications

Known hypersensitivity to active ingredient. Also contraindicated in patients suffering from phenylketonuria and peptic ulcer.

Side Effects

Generally, Acetylcysteine is well tolerated. However, mild effects such as nausea, headache, tinnitus, urticaria, stomatitis, rhinorrhoea, chills, fever, bronchospasm may be observed. Occasional cases of nausea and dyspepsia, rare cases of urticaria may be observed.

Pregnancy & Lactation

Pregnancy Category B. Caution should be taken in case of pregnancy & lactation while using Acetylcysteine.

Precautions

Acetylcysteine should be given in caution in asthma patients.

Overdose Effects

Accidental overdose of Acetylcysteine may cause nausea, vomiting or diarrhea.

Storage Conditions

Protect from light & moisture, store below 25° C. Keep all medicines out of the reach of children.