Is ipratropium (anticholinergic bronchodilator) effective for treating pertussis cough in adults and children?

Ipratropium for Pertussis Cough

Ipratropium bromide is NOT effective for treating the characteristic paroxysmal cough of pertussis (whooping cough) and should not be used for this indication. 1

Evidence Against Ipratropium for Pertussis

The most definitive evidence comes from a Cochrane systematic review that specifically evaluated symptomatic treatments for whooping cough, including salbutamol (a beta-2 agonist similar in mechanism to ipratropium's bronchodilator effects). This review found no statistically significant benefit for any intervention aimed at suppressing the paroxysmal cough in pertussis. 1

• Salbutamol showed no change in coughing paroxysms per 24 hours (mean difference -0.22,95% CI -4.13 to 3.69) 1
• The review concluded that insufficient evidence exists to support any intervention for the cough in whooping cough 1
• Nine studies were analyzed, though all were small and performed in industrialized settings 1

Why Ipratropium Works for Other Post-Infectious Coughs But NOT Pertussis

Post-Infectious Cough (Non-Pertussis)

For typical post-infectious cough following upper respiratory infections, ipratropium bromide IS recommended as first-line therapy with fair quality evidence (Grade B). 2, 3

• A controlled trial demonstrated that inhaled ipratropium (320 mcg/day) significantly reduced day and night-time cough in non-smoking adults with protracted post-viral cough 4
• The ACCP guidelines specifically recommend considering ipratropium for post-infectious cough as it may attenuate symptoms 2, 5
• Twelve of 14 patients showed overall clinical improvement, with five achieving complete resolution 4

The Critical Distinction: Pertussis is Different

The ACCP guidelines explicitly state that their recommendations for ipratropium apply to "postinfectious cough, not due to bacterial sinusitis or early on in a Bordetella pertussis infection." 2

• Pertussis causes a uniquely virulent form of post-infectious cough with distinct pathophysiology 2
• The characteristic paroxysmal cough, post-tussive vomiting, and inspiratory whooping sound indicate a different mechanism than typical post-viral cough 2
• Pertussis toxin and other virulence factors cause specific airway damage that does not respond to anticholinergic bronchodilation 2

What DOES Work for Pertussis

Early-Stage Treatment (First 1-2 Weeks)

Macrolide antibiotics are the only evidence-based treatment for pertussis, but ONLY when administered early in the disease course. 2

• Antibiotics reduce transmission and should be started as soon as pertussis is suspected 2
• Patients should be isolated for 5 days from the start of antibiotic treatment 5
• After the paroxysmal stage begins, antibiotics do not reduce cough severity or duration 2

Symptomatic Management

No intervention has proven effective for the established paroxysmal cough of pertussis. 1

• Corticosteroids showed no clear benefit (mean reduction in hospital stay -3.5 days, 95% CI -15.3 to 8.4) 1
• Pertussis immunoglobulin showed no significant change in hospital stay or whooping episodes 1
• Diphenhydramine did not reduce coughing spells 1

Clinical Algorithm

When Cough Presents After URI:

1. If cough has typical post-viral features (no paroxysms, no post-tussive vomiting, no whooping):

   • Start ipratropium bromide 36 μg (2 inhalations) four times daily 3
   • Expect improvement within days to weeks 3

2. If cough lasts ≥2 weeks with paroxysms, post-tussive vomiting, or inspiratory whooping:

   • Suspect pertussis and obtain nasopharyngeal culture (gold standard) 5
   • Do NOT use ipratropium 2, 1
   • Start macrolide antibiotics immediately if within first 1-2 weeks of illness 2
   • Isolate patient for 5 days after starting antibiotics 5

3. If pertussis is confirmed but paroxysmal stage is established:

   • Provide supportive care only 1
   • Counsel that cough will resolve over weeks to months regardless of treatment 2
   • Continue antibiotics only to reduce transmission, not for symptom relief 2

Common Pitfalls to Avoid

• Do not assume all post-infectious coughs are the same - pertussis requires specific recognition and different management 2
• Do not delay antibiotic treatment if pertussis is suspected early in the illness, as this is the only window for effective intervention 2
• Do not waste resources on symptomatic treatments for established pertussis cough, as none have proven effective 1
• Do not forget isolation precautions - pertussis is highly contagious in both children and adults 2