Introduction 

A cough is a reflex action to clear your airways of mucus and irritants such as dust or smoke. It's rarely a sign of anything serious.
A "dry cough" means it's tickly and doesn't produce any phlegm (thick mucus). A "chesty cough" means phlegm is produced to help clear your airways.
Most coughs clear up within three weeks and don't require any treatment. For more persistent coughs, it's a good idea to see your GP so they can investigate the cause.

What can cause a cough?

Some of the main causes of short-term (acute) and persistent (chronic) coughs are outlined below.

Short-term coughs

Common causes of a short-term cough include:
  • an upper respiratory tract infection (URTI) that affects the throat, windpipe or sinuses – examples are a cold,flu,laryngitis,sinusitis or whooping cough
  • a lower respiratory tract infection (LRTI) that affects your lungs or lower airways – examples are acute bronchitis or pneumonia
  • An allergy, such as allergic rhinitis or hay fever
  • a 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.