Chronic Cough: Common Causes and When to See a Doctor

Medications That Can Be the Hidden Cause

ACE inhibitors, a widely prescribed class of blood pressure medication, cause a persistent dry cough as a well-documented side effect in a meaningful percentage of people who take them, sometimes beginning weeks or even months after starting the medication, which makes the connection easy to miss. This cough typically resolves within days to a few weeks of switching to a different blood pressure medication class, and it's one of the more straightforward, fully reversible causes of chronic cough once correctly identified — which is exactly why reviewing current medications is a standard early step in evaluating any chronic cough.

Warning Signs That Warrant Prompt Evaluation

For a chronic cough without these warning features, evaluation for the three common causes described above — often through a combination of symptom pattern, a trial of targeted treatment, and, when needed, specific testing (spirometry for asthma, pH monitoring for reflux) — is the typical approach before considering less common causes.

Less Common but Important Causes

Chronic bronchitis, a component of chronic obstructive pulmonary disease (COPD) primarily affecting current or former smokers, produces a chronic productive cough alongside progressive breathlessness. Certain interstitial lung diseases produce a dry, persistent cough, often with breathlessness that gradually worsens over months to years. In children specifically, chronic cough has a somewhat different set of likely causes, and persistent cough in a child also warrants its own dedicated medical evaluation rather than assuming the adult causes described here directly apply.

Treatment Follows the Underlying Cause

Because chronic cough has several genuinely distinct underlying mechanisms, effective treatment depends on correctly identifying which one (or which combination) is responsible, rather than using a single generic cough suppressant approach. Post-nasal drip responds to intranasal steroids and antihistamines; cough-variant asthma responds to standard asthma controller therapy; reflux-related cough responds to acid-suppressing medication and specific dietary and positional changes (avoiding large meals before lying down, elevating the head of the bed). Over-the-counter cough suppressants, such as dextromethorphan, can provide short-term symptom relief but don't address any of these underlying causes and generally aren't a substitute for identifying and treating the actual source.