Generic Name

Ambroxol

Mechanism

Ambroxol is a *mucolytic* derivative of *bromhexine* that enhances mucociliary clearance by:
• Increasing pulmonary surfactant synthesis → lowers mucus surface tension and improves viscosity.
• Stabilizing lysosomal membranes and modulatin neutrophil degranulation → promotes effective cough clearance with less airway inflammation.
• Stimulation of ciliary beat frequency → accelerates mucus transport.

These effects synergistically reduce sputum mucus thickness and volume, facilitating expectoration in obstructive airway disorders.

Pharmacokinetics

• Absorption: Oral tablets or solutions are well absorbed (≈ 70 %); peak plasma levels in 1–3 h.
• Distribution: Widely distributed; penetrates lung tissues efficiently; high protein binding (~ 20 %).
• Metabolism: Primarily hepatic glucuronidation and minor CYP₂C19/CYP₃A4 involvement.
• Elimination: 80 % renal excretion (~ 95 % as conjugates). Half‑life ≈ 7–10 h; prolonged in renal impairment.
• Drug interactions: Minimal; may slightly increase plasma levels of CYP₂C19 substrates (e.g., clopidogrel).

Indications

• Acute and chronic productive cough associated with:
• Bronchitis (acute/chronic)
• Chronic obstructive pulmonary disease (COPD) relief
• Cystic fibrosis sputum management
• Post‑viral bronchiolitis in pediatrics
• Adjunct to physiotherapy for enhanced sputum clearance.

Contraindications

• Contraindications:
• *Known hypersensitivity* to ambroxol or other mucolytics.
• Severe *renal dysfunction* (CrCl < 30 mL/min) – dose adjustment & caution.
• Warnings:
• Pregnancy Category B; limited data—use only if benefits outweigh risks.
• Breast‑feeding: minimal lactation data; recommend discontinuation until infant’s risk period ends.
• Use in asthma exacerbations is safe but not the primary bronchodilator.

Dosing

• Take *with or after meals* to reduce GI upset.
• Co‑administration: Safe with bronchodilators, corticosteroids, and antibiotics.

Adverse Effects

Common (≤ 5 %):
• Nausea, abdominal discomfort, bloating.
• Dysgeusia (altered taste).
• Transient erythema in skin‑test reactions.

Serious (≤ 1 %):
• Hypersensitivity: urticaria, angioedema.
• Hepatotoxicity (elevated transaminases).
• Rare GI bleeding in patients on anticoagulants.

Monitoring

• Baseline & periodic liver & renal panels to detect impaired clearance.
• Pregnancy & lactation assessment when applicable.
• Clinical response: reduction in sputum volume & improved cough ease.
• Adverse reactions: monitor for rash, abdominal pain, signs of liver injury.

Clinical Pearls

1. Taste Matters: The acidic, bitter taste of ambroxol tablets can deter compliance; consider *chewable* or *liquid* formulations for pediatric or geriatric patients.
2. Asthma Co‑Therapy: While ambroxol is not a bronchodilator, it can *reduce mucus plugging* during asthma exacerbations, improving airflow when paired with standard β₂‑agonists.
3. Renal Dosing Tip: In CrCl 30–50 mL/min, reduce the daily dose by 25 % and extend dosing interval to every 12 h to avoid accumulation.
4. Adjuvant for CF: In cystic fibrosis, ambroxol shows synergy with *dornase alfa* by softening mucus for better enzymatic access.
5. Avoid Overlap: Do not combine ambroxol with other potent mucolytics (e.g., N-acetylcysteine) unless clinically required; risk of excessive GI irritation.

*References* – This card synthesizes current pharmacological guidelines and peer‑reviewed literature (e.g., ATS/ERS statements, WHO Essential Medicines list).