Cough is a defense mechanism of the body — essential for protecting and clearing the airways. In many cases it is temporary and self-limiting, as in colds and flu. But when cough persists for more than 8 weeks, it becomes chronic and indicates that something needs investigation. Chronic cough is rarely an isolated problem — it is usually the signal of an underlying condition that deserves proper diagnosis and treatment.
Most common causes
Allergic rhinitis and post-nasal drip — nasal secretion dripping down the throat
Asthma — especially cough-variant asthma
Gastroesophageal reflux — even without heartburn, acid can irritate the airways
COPD — in current or former smokers
Medications — some antihypertensives (ACE inhibitors) cause cough as a side effect
Bronchiectasis — secretion buildup in the bronchi
Interstitial diseases — when cough is dry and persistent
When to seek urgent investigation
- Coughing up blood
- Unexplained weight loss associated with cough
- Prolonged fever accompanied by cough
- Progressive shortness of breath
- Cough appearing in a current or former heavy smoker
How diagnosis is made
There is no single test for chronic cough. Investigation is systematic:
Detailed clinical evaluation — history, triggers, cough characteristics
Spirometry to investigate asthma or COPD
- Chest X-ray or CT scan
Reflux evaluation when indicated
Upper airway investigation — rhinitis, sinusitis
Treatment
Treatment depends on the identified cause. Treating the origin is far more effective than using syrups or cough suppressants without a diagnosis. With the correct diagnosis, the vast majority of chronic cough cases achieve satisfactory resolution — and the person returns to breathing and living with quality.