Overview

A chronic cough is a cough that lasts eight weeks or longer in adults, or four weeks in children. A chronic cough is more than just annoying. It can interrupt your sleep and leave you feeling very tired. Severe cases of chronic cough can cause vomiting and lightheadedness, and even break a rib.

The most common causes are tobacco use and asthma. Other common causes include fluid that drips from the nose down the back of the throat, called postnasal drip, and the backward flow of stomach acid into the tube that connects the throat to the stomach, called acid reflux. Fortunately, chronic cough usually goes away once the underlying issue is treated.

Symptoms

A chronic cough can occur with other symptoms, including:

  • A runny or stuffy nose.
  • A feeling of liquid running down the back of your throat, also known as postnasal drip.
  • Clearing your throat a lot.
  • Sore throat.
  • Hoarseness.
  • Wheezing and shortness of breath.
  • Heartburn or a sour taste in your mouth.
  • In rare cases, coughing up blood.

When to see a doctor

See your healthcare professional if you have a cough that lasts for weeks, especially one that brings up sputum or blood, disturbs your sleep, or affects school or work.

Causes

A cough that happens once in a while is common. It helps clear irritants and mucus from your lungs and prevents infection. But a cough that lasts for weeks is usually due to a health concern. Many times, more than one health concern causes the cough.

Most cases of chronic cough are due to these causes, which can occur alone or together:

  • Postnasal drip. When your nose or sinuses produce extra mucus, it can drip down the back of your throat and cause you to cough. This condition also is called upper airway cough syndrome.
  • Asthma. An asthma-related cough may come and go with the seasons. It may appear after an upper respiratory tract infection. Or it can get worse when you're exposed to cold air or certain chemicals or fragrances. In one type of asthma known as cough-variant asthma, a cough is the main symptom.
  • Gastroesophageal reflux disease. In this common condition, also called GERD, stomach acid flows back into the tube that connects your stomach and throat. This tube is also known as your esophagus. The constant irritation can lead to chronic coughing. Then the coughing can make GERD worse, creating a vicious cycle.
  • Infections. A cough can last long after other symptoms of pneumonia, flu, a cold or another infection of the upper respiratory tract have gone away. A common cause of a chronic cough in adults — but one that often isn't recognized — is whooping cough, also known as pertussis. Chronic cough also can occur with fungal infections of the lung, as well as tuberculosis infection, also called TB, or lung infection with nontuberculous mycobacteria, also called NTM. NTM is found in soil, water and dust.
  • Chronic obstructive pulmonary disease (COPD). Also called COPD, this is a lifelong inflammatory lung disease that limits airflow from the lungs. COPD includes chronic bronchitis and emphysema. Chronic bronchitis can cause a cough that brings up colored sputum. Emphysema causes shortness of breath and damages the air sacs in the lungs, also known as alveoli. Most people with COPD are current or former smokers.
  • Blood pressure drugs. Angiotensin-converting enzyme inhibitors, also called ACE inhibitors, which are commonly prescribed for high blood pressure and heart failure, are known to cause chronic cough in some people.

Less commonly, chronic cough may be caused by:

  • Aspiration — when food or other items are swallowed or inhaled and go into the lungs.
  • Bronchiectasis — widened and damaged airways that slowly lose the ability to clear out mucus.
  • Bronchiolitis — an infection that causes swelling, irritation and buildup of mucus in the small airways of the lung.
  • Cystic fibrosis — a genetic disorder that affects the lungs, digestive system and other organs.
  • Idiopathic pulmonary fibrosis — gradual damage and scarring of the lungs due to a cause that isn't known.
  • Lung cancer — cancer that starts in the lungs, including non-small cell lung cancer and small cell lung cancer.
  • Nonasthmatic eosinophilic bronchitis — when airways are inflamed but asthma is not the cause.
  • Sarcoidosis — groups of inflamed cells that form lumps or nodules in different parts of the body but most often in the lungs.

Risk factors

Being a current or former smoker is one of the leading risk factors for chronic cough. Exposure to a lot of secondhand smoke also can lead to coughing and lung damage.

Complications

Having a cough that doesn't stop can be very tiring. Coughing can cause various concerns, including:

  • Sleep disruption.
  • Headache.
  • Dizziness.
  • Vomiting.
  • Sweating a lot.
  • Unintended bladder loss, also known as urinary incontinence.
  • Broken ribs.
  • Passing out, also known as syncope.
By Mayo Clinic Staff