Evaluation and Management of Persistent Dry Cough

Initial Assessment

The American Thoracic Society recommends obtaining a chest radiograph immediately to exclude pneumonia, structural abnormalities, masses, interstitial disease, or congestive heart failure in patients with chronic cough 1, 2
Stopping ACE inhibitor medication can lead to resolution of cough within days to 2 weeks (median 26 days) in patients with chronic cough 3, 4
Smoking cessation can lead to resolution of chronic bronchitis within 4 weeks in most patients 3
Systemic symptoms such as fever, night sweats, weight loss, or history of tuberculosis, cancer, or AIDS require expanded differential diagnosis in patients with chronic cough 3
Cough lasting >8 weeks qualifies as chronic cough in adults, according to the American College of Chest Physicians 2, 1

The American College of Allergy, Asthma, and Immunology recommends initiating empiric therapy with a first-generation antihistamine-decongestant combination for 1-2 weeks in patients with upper airway cough syndrome (UACS) 1, 5
Nasal discharge, throat clearing, or postnasal drip sensation are clinical pointers for UACS 1
Nasal congestion or rhinorrhea are also clinical pointers for UACS 5
If UACS treatment fails, proceed to asthma evaluation, which may involve spirometry with bronchodilator response or bronchoprovocation challenge, according to the National Asthma Education and Prevention Program 1
Suspect asthma when cough worsens at night, with cold air exposure, or with exercise, and response to bronchodilators occurs within 1 week, with complete resolution potentially taking up to 8 weeks 6, 1, 5
If both UACS and asthma treatments fail, initiate intensive GERD therapy, including high-dose PPI therapy, dietary modifications, and lifestyle changes, as recommended by the American Gastroenterological Association 1, 5
GERD therapy requires patience, as response may take 2 weeks to several months, with some patients requiring 8-12 weeks before improvement 5, 7

Proceed to advanced testing only after adequate therapeutic trials of UACS, asthma, and GERD have failed, according to the American College of Chest Physicians 1
Order high-resolution CT (HRCT) chest to evaluate for bronchiectasis, interstitial lung disease, or occult masses 1
Order 24-hour esophageal pH monitoring to evaluate for GERD-related cough if empiric therapy failed 7
Order bronchoscopy to evaluate for endobronchial lesions, sarcoidosis, eosinophilic bronchitis, or occult infection 1

Only diagnose unexplained cough after completing systematic evaluation and adequate therapeutic trials of all common causes, as recommended by the American College of Chest Physicians 4, 1
Consider gabapentin trial starting at 300mg once daily, escalating as tolerated to maximum 1,800mg daily in divided doses, for truly refractory cough 1
Multimodality speech pathology therapy is a reasonable alternative approach for truly refractory cough 1
Low-dose morphine may be considered but carries addiction risk, according to the American Academy of Sleep Medicine 8

If cough began with an acute respiratory infection 3-8 weeks ago, consider post-infectious cough, as recommended by the American College of Chest Physicians 8
Treatment options for post-infectious cough include inhaled ipratropium as first-line therapy, inhaled corticosteroids if ipratropium fails, and short course of oral prednisone for severe paroxysms after ruling out other causes 8

The absence of fever and cold symptoms does not exclude Upper Airway Cough Syndrome (UACS), as chronic rhinosinusitis can present with minimal nasal symptoms, according to the American Thoracic Society 9
Cough may be the only manifestation of asthma, occurring without wheezing or dyspnea, as stated by the American College of Chest Physicians 9
Normal spirometry does not exclude the diagnosis of asthma; bronchoprovocation testing may be required, as recommended by the American Thoracic Society 9
GERD-associated cough frequently occurs without any gastrointestinal symptoms such as heartburn or regurgitation, according to the American Gastroenterological Association 9

No patient with troublesome cough should continue ACE inhibitors, as they can cause chronic dry cough in 5-35% of patients, as stated by the American Heart Association 9
Chronic exposure to irritants (smoke, chemicals, dust) can cause persistent dry cough without systemic symptoms, according to the American College of Chest Physicians 10
A thorough occupational history is mandatory to diagnose environmental or occupational irritant exposure, as recommended by the American Thoracic Society 9

Beta-blockers, inhaled medications, nitrofurantoin, and mycophenolate mofetil can cause chronic dry cough, as stated by the American College of Chest Physicians 10
Eosinophilic bronchitis presents with chronic dry cough, normal spirometry, and no airway hyperresponsiveness, according to the American Thoracic Society 9

The absence of fever, abnormal vital signs, and focal chest findings makes pneumonia unlikely, but chest radiography is mandatory to definitively exclude this diagnosis, as recommended by the American College of Emergency Physicians 11
Chest radiography will help exclude congestive heart failure, according to the American Heart Association 11
Consider tuberculosis if the patient has resided in endemic areas, has HIV risk factors, or has unexplained weight loss, as stated by the American Thoracic Society 12

Do not diagnose acute bronchitis in the absence of an acute viral upper respiratory infection, as this leads to inappropriate antibiotic prescribing, as stated by the American Academy of Family Physicians 13
Do not assume purulent sputum indicates bacterial infection; it commonly occurs with viral infections due to neutrophil influx, according to the American College of Emergency Physicians 11

Obtain chest radiograph and spirometry immediately, as recommended by the American Thoracic Society 9
Consider advanced testing (HRCT, bronchoscopy, 24-hour pH monitoring) only after adequate therapeutic trials have failed, as stated by the American College of Chest Physicians 9