It is normal to cough occasionally, especially if you have a cold, flu or allergies.
Coughing has a purpose. It is your body’s way of keeping unwanted stuff from getting into your lungs. Coughing helps clear extra mucus from your airways (small tubes in your lungs). This extra mucus could be caused by smoking, a cold, nasal or sinus problems, a lung infection or a lung disease like asthma or COPD.
A cough may be caused by a condition not related to your lungs, such as heartburn, some medications, or throat irritants (for example, dust, pollution, or chemicals in your workplace or home).
Coughing up blood or thick mucus is not normal. If your cough makes you very tired or light-headed, causes chest or stomach pain, or causes you to wet yourself, you should talk to your doctor.
What are the different types of cough?
Doctors divide coughing into three groups, based on how long the cough has lasted: acute (coughing less than three weeks), sub-acute (coughing that lasts from three to eight weeks), or chronic (coughing that lasts longer than eight weeks). Those who have a persistent cough, wheezy chest or breathlessness should talk to their health-care professional about a spirometry test.