Treatment for Cough

Drugs for Cough

Introduction to Cough and Its Management

• Definition: Cough is a protective reflex to clear airways.
• Types: Productive (wet) and Non-productive (dry).
• Drug Categories: Expectorants & Antitussives

Classification of Drugs for Cough

1. Expectorants – Increase bronchial secretion or reduce mucus viscosity
• Examples: Guaiphenesin, Potassium citrate, Bromhexine, Ambroxol, Levodropropizine, Carbocisteine, Acetylcysteine, Ammonium Chloride
2. Antitussives – Suppress the cough reflex
• Examples: Codeine, Pholcodeine, Ethylmorphine, Noscapine, Dextromethorphan, Chlorpheniramine, Diphenhydramine, Promethazine

Guaiphenesin

• Mechanism: Increases hydration of respiratory tract, thinning mucus
• Indication: Productive cough
• Adverse Effects: Nausea, dizziness
• Interactions: None significant

Potassium Citrate

• Mechanism: Alkalinizes urine, mild expectorant by soothing effect
• Indication: Bronchitis, cystitis
• Adverse Effects: GI upset, hyperkalemia (rare)
• Interactions: Potassium-sparing diuretics

Bromhexine & Ambroxol

• Mechanism: Mucolytic, breaks down mucopolysaccharide fibers in mucus
• Indication: Chronic bronchitis, asthma
• Adverse Effects: GI discomfort, hypersensitivity
• Interactions: Antibiotic absorption may increase

Levodropropizine

• Mechanism: Peripheral antitussive, inhibits sensory nerve activity
• Indication: Non-productive cough
• Adverse Effects: Drowsiness, nausea
• Interactions: Avoid with other CNS depressants

Carbocisteine & Acetylcysteine

• Mechanism: Breaks disulfide bonds in mucus, reducing viscosity
• Indication: COPD, cystic fibrosis
• Adverse Effects: GI upset, bronchospasm (inhaled forms)
• Interactions: Antitussives (reduce mucus clearance)

Ammonium Chloride

• Mechanism: Irritant action on respiratory tract → reflex increase in secretions
• Indication: Expectorant in combination cough syrups
• Adverse Effects: GI irritation, metabolic acidosis (large doses)
• Interactions: Avoid with acidifying agents

Codeine, Pholcodeine, Ethylmorphine

• Mechanism: Central acting opioid agonists suppress cough center
• Indication: Dry cough
• Adverse Effects: Constipation, drowsiness, dependence
• Interactions: CNS depressants, alcohol

Noscapine

• Mechanism: Non-narcotic central antitussive
• Indication: Non-productive cough
• Adverse Effects: Nausea, dizziness
• Interactions: Limited, avoid CNS depressants

Dextromethorphan

• Mechanism: NMDA receptor antagonist, suppresses medullary cough center
• Indication: Dry cough
• Adverse Effects: Drowsiness, confusion, abuse potential
• Interactions: MAO inhibitors (risk of serotonin syndrome)

Antihistamines as Antitussives

• Drugs: Chlorpheniramine, Diphenhydramine, Promethazine
• Mechanism: H1-receptor antagonists, reduce cough via sedative & anticholinergic action
• Indication: Allergic cough, upper respiratory tract infections
• Adverse Effects: Sedation, dry mouth, dizziness
• Interactions: Potentiation with alcohol, sedatives

Presentation for Drugs for Cough

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