• Top 3 causes: postnasal drip, asthma, gastroesophageal reflux disease (GERD)

Pulmonary infectious

• Postviral
• Bronchitis, especially in smokers
• Bronchiectasis
• Tuberculosis
• Cystic fibrosis
• Mycobacterium avium complex (MAC)
• Pertussis
• Mycoplasma
• Chlamydia
• Respiratory syncytial virus (RSV)
• Parasites, eg, ascariasis, paragonimiasis

Pulmonary noninfectious

• Asthma (cough-variant asthma)
• Beta-blockers causing asthma
• Chronic obstructive pulmonary disease (COPD)
• ACE inhibitors
• Irritant inhalation, eg, smoking
• Endobronchial lesion, eg, tumor
• Interstitial lung disease
• Sarcoidosis
• Chronic microaspiration

Nonpulmonary

• Gastroesophageal reflux disease (GERD)
• Postnasal drip (allergic rhinitis)
• Sinusitis
• Congestive heart failure (CHF)
• Laryngitis
• Ear canal or tympanic membrane irritation
• Psychogenic or habit cough

• Acute cough