Best Initial Medication for Non-Productive Cough
For non-productive cough in patients with potential asthma or COPD, start with ipratropium bromide (inhaled anticholinergic) as first-line therapy, as it addresses both the underlying bronchospasm and provides direct cough suppression with Grade A evidence. 1, 2
Treatment Algorithm by Clinical Context
If COPD or Chronic Bronchitis is Present or Suspected
Primary therapy should target the underlying airway disease first:
Ipratropium bromide 500 µg via nebulizer is the only inhaled anticholinergic with Grade A evidence for cough suppression in chronic bronchitis, offering substantial benefit for both bronchodilation and direct cough control 1, 2, 3
Short-acting β-agonists (albuterol 5 mg or terbutaline 10 mg nebulized) should be used to control bronchospasm and relieve dyspnea; in some patients this also reduces chronic cough (Grade A recommendation) 1
For acute exacerbations: Start with short-acting β-agonist; if no prompt response, add ipratropium bromide 500 µg to the β-agonist after maximal dosing of the first agent 1
If Asthma is Suspected
Treat the underlying bronchial hyperresponsiveness:
Empiric trial of inhaled corticosteroids combined with inhaled β-agonists or oral leukotriene inhibitors should be administered before considering pure cough suppressants 1
Bronchoprovocation challenge testing ideally should guide therapy, but empiric antiasthma treatment is appropriate when testing is unavailable 1
For Pure Symptomatic Cough Suppression (When Underlying Disease is Treated or Absent)
Dextromethorphan is the preferred centrally-acting suppressant:
Dextromethorphan 60 mg provides maximum cough reflex suppression and is superior to standard OTC dosing of 15-30 mg, which is often subtherapeutic 2, 3
Maximum daily dose should not exceed 120 mg 3
This agent has a superior safety profile compared to codeine, without sedation, constipation, or physical dependence risk 2, 3
Codeine should NOT be prescribed despite its historical use—it has no greater efficacy than dextromethorphan but carries significantly more adverse effects including drowsiness, nausea, constipation, and dependence 2, 3
Evidence shows codeine and dextromethorphan suppress cough counts by 40-60% in chronic bronchitis, though studies used small patient populations 1
Critical Clinical Pitfalls to Avoid
Do not suppress productive cough as secretion clearance serves a protective function, particularly in COPD patients 1, 3
Avoid first-generation antihistamines (diphenhydramine, promethazine, chlorpheniramine) in elderly patients due to significant anticholinergic effects, sedation, and fall risk, despite their common use in combination products 2
Do not use theophylline during acute exacerbations of chronic bronchitis (Grade D recommendation), though it may be considered for stable chronic bronchitis with careful monitoring 1
Mucokinetic agents and expectorants lack evidence for cough control in chronic bronchitis and should not be used for this indication 1
Check for ACE inhibitor use as a reversible cause—if present, the drug should be stopped and replaced 1
Duration and Monitoring
Antitussive therapy should be limited to short-term use (typically less than 7 days) 3
If cough persists beyond 3 weeks, discontinue antitussive therapy and pursue full diagnostic workup 3
For chronic bronchitis patients requiring ongoing therapy, ipratropium bromide can be continued long-term as it treats both the underlying disease and cough 1, 2