Cough is a defensive reflex mechanism that clears secretions from the upper airways of the respiratory tract, triggered by the stimulation of a complex reflex arc. In other words, it is a voluntary or involuntary action that clears the throat of fluids, irritants, foreign particles and microbes.

Types of Cough

Cough in adults is classified as acute, subacute, or chronic based on duration. Acute cough lasts up to three weeks, subacute cough lasts three to eight weeks, and chronic cough lasts longer than eight weeks. A cough can be non-productive (dry) or productive (when sputum/phlegm is coughed up).

Causes of cough


Some causes of cough can be short-term (acute) or persistent (chronic), these possible causes are:

For short-term coughs, common causes include:

  • Upper respiratory tract infection (URTI) that affects the throat, windpipe or sinuses leading to cold, flu, laryngitis, sinusitis or whooping cough.
  • Lower respiratory tract infection (LRTI) that affects the lungs or lower airways resulting in acute bronchitis or pneumonia.
  • Allergy, such as allergic rhinitis or hay fever.
  • Flare-up of a long-term condition such as asthma, chronic obstructive pulmonary disease (COPD) or chronic bronchitis.
  • inhaled dust or smoke

In rare cases, a short-term cough may be the first sign of a health condition that causes a persistent cough.

Common causes of persistent coughs are:

  • Long-term respiratory tract infection, such as chronic bronchitis.
  • Asthma, which usually causes other symptoms, such as wheezing, chest tightness and shortness of breath.
  • Allergy.
  • Smoking.
  • Bronchiectasis which makes the airways of the lungs to become abnormally widened.
  • Postnasal drip (mucus dripping down the throat from the back of the nose) caused by rhinitis or sinusitis.
  • Gastro-esophageal reflux disease (GORD) where the throat becomes irritated by leaking stomach acid.
  • Prescribed medication such as an angiotensin-converting enzyme inhibitor (ACE inhibitor) used to treat high blood pressure and cardiovascular disease.

In addition, a persistent cough can be a symptom of a more serious condition, such as lung cancer, heart failure, a pulmonary embolism (blood clot on the lung) or tuberculosis.


Preventive measures to avoid a cough

  1. Quit smoking or avoid passive smoking.
  2. Keep your immune system strong through natural nutrition, regular vigorous exercise, strong nerve force and regular natural good sleep boosts your body’s defense against these viruses that cause colds.
  3. Maintain good hydration
  4. Keep warm and hot showers
  5. Eat healthy diets, especially those high in fruit, fiber, and flavonoids.
  6. Stay away from anyone suffering from contagious illnesses, such as bronchitis, to avoid coming into contact with germs.
  7. If you have existing medical conditions that increase the chances of developing a cough, such as GERD or asthma, consult your doctor about different management strategies.

Diagnostic approach

Cough is diagnosed by checking a patient’s history, as well as the duration, character, quality, and timing of the cough. Further test such allergy tests, breathing tests, x-rays, and spirometry may be carried out.


Treatment of cough

The treatment of a cough is based on the underlying cause. For example;

  • Asthma can be treated with inhaled steroids to reduce inflammation in the airways.
  • Allergies can be treated by avoiding things you’re allergic to and taking antihistamines to dampen down your allergic reactions.
  • Bacterial infections can be treated with antibiotics.
  • Gastro-oesophageal reflux disease (GORD) can be treated with antacids to neutralise your stomach acid and medication to reduce the amount of acid your stomach produces.
  • Chronic obstructive pulmonary disease (COPD) can be treated with bronchodilators to widen your airways
  • And if you smoke, quitting is also likely to help improve your cough.


Compiled by: eDokita Team


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  2. Kian Fan Chung, John G. Widdicombe and Homer A. Boushey. Cough: Causes, Mechanisms and Therapy. ISBN 1-4051-1634-X, 2003011068.
  3. NHS Choices. Cough. 2015. Web
  4. Cough. 2017. Web
  5. Manuel Hernandez and John P. Cunha. eMedicineHealth. 2016

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