Mucolytic Pregnancy: Although tests in mammalian species have revealed no teratogenic effects, carbocisteine is not recommended during the first trimester of pregnancy. It is unknown whether carbocisteine/metabolites are excreted in human milk.

Carbocisteine (ENT — Mucolytic)

Brand names: Mucodyne

Carbocisteine is a mucolytic used to reduce sputum viscosity in chronic productive cough, including chronic obstructive pulmonary disease, making secretions easier to expectorate.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 2250 mg daily in divided doses initially, reducing to 1500 mg daily in divided doses when a satisfactory response is obtained

Route: Oral

Frequency: In divided doses - e.g. 15 mL of the 250 mg/5 mL syrup three times a day, reducing to 10 mL three times a day

Adults: dosage is based upon an initial daily dosage of 2250 mg carbocisteine in divided doses, reducing to 1500 mg daily in divided doses when a satisfactory response is obtained (e.g. for normal syrup 15 mL three times a day reducing to 10 mL three times a day). Paediatric population (from the same SPC, volume-based rather than per-kg): 2-5 years 1.25-2.5 mL four times a day; 6-12 years 5 mL three times a day; carbocisteine is contraindicated in children aged less than 2 years. Use the measuring device provided - the oral syringe is graduated per 0.25 mL and one 0.25 mL graduation corresponds to 12.5 mg of carbocisteine. Product: Carbocisteine 250 mg/5 mL syrup.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Use in children less than 2 years of age
Active peptic ulceration
Hypersensitivity to the active substance or to any of the excipients

Side effects

Nausea, vomiting and diarrhoea (uncommon)
Urticaria and bronchospasm (rare) - special attention in asthmatic patients; discontinue treatment if this occurs
Headache, dizziness, muscle pain, palpitations (rare)
Gastrointestinal bleeding (very rare)
Stevens-Johnson syndrome, erythema multiforme (frequency not known)
Hypothyroidism (frequency not known) - special attention in patients with compromised thyroid function

Interactions

No drug interactions have been identified (SPC section 4.5)
Association with antitussive medication is not recommended (SPC section 4.4)

Clinical monograph

How it works

It alters the composition of bronchial mucus, reducing its viscosity and improving clearance of secretions from the airways.

Prescribing in practice

Avoid in active peptic ulcer disease, as it can affect the gastric mucosal barrier; use with caution in those with a history of peptic ulceration.
Review the benefit after a defined trial period and stop if there is no symptomatic improvement.
Gastrointestinal upset and, rarely, gastrointestinal bleeding have been reported.

Monitoring

Assess the response to treatment clinically by reduction in cough and ease of expectoration, and review whether continued use is justified. No routine laboratory monitoring is required.

Counselling the patient

Stop and seek advice if you develop stomach pain, indigestion or signs of bleeding such as black stools.
Tell your prescriber if you have ever had a stomach ulcer.
Let your prescriber know if your symptoms do not improve so treatment can be reviewed.

Evidence & guidelines

Used as adjunctive symptomatic therapy in chronic productive cough and COPD where mucus clearance is problematic.

Reference: ENT-UK Sinusitis Guidelines; Cochrane Review; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Drugs

Pathways