N-acetylcysteine

Registered South African indications:

• Respiratory conditions
• Cystic fibrosis
• Paracetamol overdose

Contraindications

• Hypersensitivity to the active ingredient or any of its excipients
• Safety in pregnancy has not been established
• Active peptic ulceration
• In children below 2 years of age

Cautions

• Breastfeeding
• Renal impairment
• Hepatic impairment
• Bronchial asthma
• Patients unable to expectorate efficiently
• History of peptic ulcer
• Children and adolescents
• Fructose intolerance (certain formulations (sac))
• Sodium-restricted diet (certain formulations (eft))

Forms avail. in SA and covered in this monograph: eft, loz, sac

Mucolytic adjuvant in the therapy of respiratory disorders

• Oral (sac, loz): 200mg, 8hrly; Max: 600mg/24hrs
• Oral (eft): 200mg, 8hrly OR 600mg, dly

Mucolytic therapy in cystic fibrosis

• Oral (sac, loz): 200-400mg, 8hrly OR 10-30mg/kg/day
• Oral (eft): 200mg, 8hrly

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Sac: Dissolve the contents of one sachet completely in a glass containing a little water just before use, stirring as needed

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Eft: Dissolve the tablet in half a glass of water. Consume solution immediately  

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Abundant fluid intake supports the mucolytic effect of acetylcysteine

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Paracetamol overdose

• Oral (sac, loz): Loading dose: 140mg/kg; THEN 70mg/kg, 4hrly for 17 doses

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Therapy must start as soon as possible. There are indications that it is still effective up to 16hrs (or longer) after the ingestion of the paracetamol

Paed. forms avail in SA and covered in this monograph: eft, loz, sac

Mucolytic adjuvant in the therapy of respiratory disorders

Younger than 2 years

• Contraindicated

Between 2-6 years

• Oral (sac, loz ,eft): 200mg, 12hrly

Older than 6 years

• See adult dosage

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The 600mg eft is contraindicated in children <2 years and the safety and efficacy has not been established for use in children and adolescents >2 years

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Mucolytic therapy in cystic fibrosis

Younger than 2 years

• Contraindicated

Between 2-6 years

• Oral (sac, loz): 200mg, 8hrly
• Oral (eft): 200mg, 12hrly

Older than 6 years

• Oral (sac, loz, eft): See adult dosage

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Sac: Dissolve the contents of one sachet completely in a glass containing a little water just before use, stirring as needed

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Eft: Dissolve the tablet in half a glass of water. Consume solution immediately  

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Abundant fluid intake supports the mucolytic effect of acetylcysteine

Pregnancy

• Caution
• Animal studies do not indicate direct or indirect harmful effects with respect to reproductive toxicity. As a precautionary measure, it is preferable to avoid the use of acetylcysteine during pregnancy

Breastfeeding

• Caution
• There is insufficient information on the excretion of acetylcysteine in human milk. A risk to the newborns/ infants cannot be excluded

Renal Impairment

• Caution; no information available

Hepatic Impairment

• Caution; no information available

Elderly

• No dose adjustment recommended
  Patients with a reduced cough reflex are advised to take the eft in the mornings

Porphyria Information

• Not porphyrinogenic (NP)

Drugs in Sport

• Permitted - No warnings

Central Nervous System Disorders

• Headache

Cardiovascular Disorders

• Hypotension
• Tachycardia
• Haemorrhage

Respiratory Disorders

• Bronchospasm
• Dyspnoea

Gastrointestinal Disorders

• Nausea and vomiting
• Abdominal pain
• Diarrhoea
• Stomatitis
• Dyspepsia

Skin and Subcutaneous Tissue Disorders

• Rash
• Angioedema
• Pruritus
• Urticaria
• Stevens-Johnson syndrome
• Toxic epidermal necrolysis
• Recurrence of skin and mucosal lesions

Immune, Blood and Lymphatic System Disorders

• Hypersensitivity
  - Bronchospasm
  - Dyspnoea
  - Pruritus
  - Urticaria
  - Rash
  - Angioedema
  - Tachycardia
• Fever
• Anaphylactic shock
  Anaphylactic/ anaphylactoid reactions
• Thrombocytopenia
• Decreased blood platelet aggregation

Sensory Disorders

• Tinnitus

Others

• Oedema of the face

• Antitussive agents
• Activated charcoal
• Oral antibiotics
• Cephalosporins
• Nitroglycerin
• Agents that irritate the mucous membrane of the gastrointestinal tract

Other interactions

• Laboratory tests

None routine. Specific cases may require

• Lung function

Interference with tests

• Acetylcysteine can cause interference with the colorimetric assay method for the determination of salicylates
• Acetylcysteine can interfere with tests for ketones in urine

Coadministration with antibiotics

• To date, the inactivation of antibiotics by acetylcysteine has been reported only in in-vitro tests, whereby the relevant substances were mixed directly with each other. However, if oral antibiotics are required, it is advised that these should be taken two hours before or after acetylcysteine

Sulfur odour

• A mild sulfur odour does not indicate a change in the medicinal product, but is a property of the active substance itself

N-acetylcysteine exerts an intense mucolytic-fluidizing action on mucous and mucopurulent secretions by depolymerizing the mucoproteic complexes and the nucleic acids which confer viscosity to the vitreous and purulent component of the sputum and other secretions. Furthermore, acetylcysteine exerts a direct antioxidant action, having a free thiol (- SH) nucleophilic group that is able to interact directly with electrophilic groups of oxidant radicals. Of particular interest is the recent finding that acetylcysteine protects α1-antitrypsin enzyme inhibiting elastase from inactivation by hypochlorous acid (HOCl), a powerful oxidant agent produced by the myeloperoxidase enzyme of activated phagocytes. Due to its molecular structure, acetylcysteine can readily cross cell membranes. Inside the cell, n-acetylcysteine is deacetylated to L-cysteine, an amino acid essential for glutathione synthesis (GSH). GSH is a highly reactive tripeptide found ubiquitously in the various tissues of animals and is essential for the maintenance of functional capacity as well as cellular morphological integrity. It is the most important protective intracellular mechanism against oxidant radicals, both exogenous and endogenous, as well as toward numerous cytotoxic substances. These features make n-acetylcysteine particularly suitable for the treatment of acute and chronic affections of the respiratory system, characterised by thick, viscous mucous and mucopurulent secretions. 

Tablet effervescent 200mg

• Acc 200 (Sandoz) 
• Amuco 200 (Austell Laboratories)
• Lithafizz (Litha)
• Mucatak (Actor)
• Muco-Acyst 200 (Unicorn Pharmaceuticals)
• Mucofizz (Pharma Dynamics)
• Trinflem (Trinity Pharma)
• Tussmuco (Pharmacare)

Tablet effervescent 600mg

• Acc 600 (Sandoz)
• Amuco 600 (Austell Laboratories)
• Mucatak (Actor)

Sachet (per sachet) 200mg

• Mucolator (Abbott)
• Solmucol (Pharmacare) originator

Sachet (per sachet) 400mg

• Solmucol (Pharmacare) originator

Lozenges (per lozenge) 100mg 

•  Solmucol (Pharmacare)