Coughing is a common reflex action that clears your throat of mucus or foreign irritants. While everyone coughs to clear their throat from time to time, a number of conditions can cause more frequent coughing.

A cough that lasts for less than three weeks is an acute cough. Most episodes of coughing will clear up or at least significantly improve within two weeks.

If your cough lasts between three and eight weeks, improving by the end of that period, it’s considered a subacute cough. A persistent cough that lasts more than eight weeks is a chronic cough.

You should see a doctor if you cough up blood or have a “barking” cough. You should also contact them if your cough hasn’t improved with a few weeks, as this could indicate something more serious.

The most common cause of a cough is a respiratory tract infection, such as a cold or flu.

Respiratory tract infections are usually caused by a virus and may last from a few days to a week. Infections caused by the flu may take a little longer to clear up and can sometimes require antibiotics.

Smoking is a common cause of coughing. A cough caused by smoking is almost always a chronic cough with a distinctive sound. It’s often known as a smoker’s cough.

A common cause of coughing in young children is asthma. Typically, asthmatic coughing involves wheezing, making it easy to identify.

Asthma exacerbations should receive treatment using an inhaler. It’s possible for children to grow out of asthma as they get older.

Some medications will cause coughing, although this is generally a rare side effect. Angiotensin-converting enzyme (ACE) inhibitors, commonly used to treat high blood pressure and heart conditions, can cause coughing.

Other conditions:

Another common condition that can cause a chronic cough is gastroesophageal reflux disease (GERD). In this condition, stomach contents flow back into the esophagus. This backflow stimulates a reflex in the trachea, causing the person to cough.

If additional symptoms develop, contact your doctor as soon as possible. Symptoms to watch out for include:

Coughing up blood or having difficulty breathing requires immediate emergency medical attention.

The common cold is a viral infection of your nose and throat (upper respiratory tract). It's usually harmless, although it might not feel that way. Many types of viruses can cause a common cold. Healthy adults can expect to have two or three colds each year. Infants and young children may have even more frequent colds

Influenza, commonly called "the flu", is an infectious disease caused by influenza viruses. Symptoms range from mild to severe and often include fever, runny nose, sore throat, muscle pain, headache, coughing, and fatigue. These symptoms typically begin 1–4 days after exposure to the virus and last for about 2–8 days.