Cough performs an essential protective function for human airways and lungs. Without an effective cough reflex we are at risk for retained secretions and aspirated material predisposing to atelectasis (collapse), infection and respiratory compromise. Cough is classified according to its duration to Acute, subacute and chronic.the list below is mainly for common causes

Acute Cough

Less than 3 weeks

  • Viral Upper respiratory infections
  • Sinusitis
  • Acute Bronchitis (viral)
  • Asthma exacerbation
  • Vocal cords dysfunction
  • Influenza
  • Pneumonia
  • Heart disease
  • High blood pressure meds (Ace Inhibitors like lisinopril)
  • GERD- Gastroesophageal reflux

Subacute Cough

3 to 8 weeks duration

  • Post infection cough syndrome (viral or mycoplasma) caused by post nasal drip and airways hyper reactivity
  • Asthma
  • Whooping cough
  • GERD (Stomach reflux)
  • Heart disease

Chronic Cough

More than 8 weeks

  • Post nasal drip (common cause)
  • GERD
  • Asthma
  • Eosinophilic bronchitis
  • Chronic Bronchitis and smoking


  • Lung neoplasm
  • Bronchiectasis (dilated infected airways with copious sputum)
  • Heart disease
  • Diffuse Parenchymal lung disease

Upper Airways Cough Syndrome

(Formerly known as post nasal drip)

Allergies, and viral infections in addition to bacterial sinus infection are frequently associated with excessive posterior nasal secretions and throat irritation that will lead to cough without experiencing any significant lungs congestion or trouble breathing

Vocal Cords Dysfunction

It means vocal cords are closing instead of opening during inspiration leading to inspiratory breathlessness, tight throat and Horace voice or stridor.

It may mimic Asthma.

It can be exacerbated by fumes, irritants, stress and exercise.


Asthma is when we have hypersensitive or or over reactive airways triggered by environmental allergens, often with genetic predisposition causing episodic inflammation in the lining of the airway and spasm in the muscles in its walls


Ace Inhibitors Cough

20% of patients taking the blood pressure medicine from the class called Ace Inhibitors (for example LISINOPRIL) will experience cough in the 1st 2 weeks and sometimes months after starting the medicine. It is caused by swelling in throat leading to constant urge to clear it by coughing. The swelling may involve the face, lips or tongue. Cough will stop after stopping the medicine. Complete resolution may take weeks.

Stomach Reflux (GERD)

Excessive acid production and weakness in the sphincter (valve) at the esophagus stomach junction with delayed stomach emptying may lead to acid secretion reflux from the stomach to the esophagus.the presence of acid in the Esophagus will cause Chest pain or heart burn and cough due to the stimulation of the Vagus nerve causing cough as reflex (reaction)

15% of the population have GERD

The usual triggers are:

  • Smoking and drinking
  • Aspirin and Ibuprofen excessive use
  • Spicy food, garlic and onion
  • Tomatoes
  • Chocolate
  • Citrus fruits and beverages

Not every cough is caused by Bronchitis or lung disease and at times the cough can be a  sign of  HEART DISEASE especially in the middle age or elderly with chronic medical conditions or no prior medical care, the usual red flags are abnormal vitals: Rapid heart beat or high blood pressure. Clinicians and Patients must be very careful !!