Persistent cough

Everyone coughs from time to time. Coughing serves a purpose. It clears particles and mucus from your respiratory tract to protect your lungs from infection and inflammation. A cough is also a common symptom of an upper respiratory tract infection, such as the flu, bronchitis or pneumonia. Most coughs only last for a week or two. However, in some cases, a cough can linger.

A lasting cough can be irritating and exhausting, especially if you have a persistent cough at night that keeps you awake. In some cases, severe chronic coughs can lead to vomiting, dizziness, hoarseness, urine leakage and rib fractures. In fact, a cough that isn't improving is one of the most common reasons for healthcare provider visits.

Know that a cough due to an illness usually resolves within a few days or weeks. But a true chronic cough tends to last much longer, sometimes lingering for several months or even years. In general, a chronic cough in adults is defined as a cough that lasts eight weeks or longer. In children, a cough may be considered persistent if it lasts four weeks or more.

Some common causes of a chronic cough include:

• Postnasal drip, which is drainage from the nose drips down the back of your throat. This can occur due to allergies, colds and other illnesses.
• Asthma, which is a lung disease that makes moving air in and out of the lungs challenging. This is the leading cause of a chronic cough in children, including toddlers.
• Gastroesophageal reflex disease (GERD), which is a condition occurs when the contents of your stomach flow backward up into the esophagus (the tube that carries food from your mouth to your stomach). GERD can cause heartburn, a sour taste in the mouth or coughing.
• Smoking and tobacco use. The cough may be due to the tobacco itself, or it may be a sign of a more serious condition, such as lung cancer or a lung infection.
• Chronic obstructive pulmonary disease (COPD), which is a condition that irritates the airways, obstructs airflow from the lungs and causes an ongoing cough. COPD includes chronic bronchitis and emphysema. Most people with COPD currently smoke or have a history of smoking.
• Infections. Sometimes, a persistent cough after a cold or other illness can last after the infection clears up. Pertussis (whooping cough) and tuberculosis can cause a lingering cough.
• Blood pressure medications. These medications, specifically angiotensin-converting-enzyme (ACE) inhibitors can cause a cough as a side effect in certain people.

Less commonly, a persistent cough can occur for other reasons. These can include aspiration (accidental breathing in of food, liquid or some other material into the lungs), heart failure, environmental irritants, emotional or psychological disorders and lung cancer.

Not all chronic coughs are the same. Some people may have a persistent, dry cough, while others have a persistent cough with phlegm. A cough may present with other symptoms. The specific symptoms depend on the cause of the cough. They may include:

• Postnasal drip
• A stuffy or runny nose
• Sneezing
• Sore throat
• Clearing your throat often
• Hoarseness
• Shortness of breath
• Wheezing (whistling sound when you breathe)
• Heartburn, indigestion or a sour taste in your mouth
• Coughing up blood

Most of the time, a chronic cough improves once the underlying problem is treated. If you keep coughing and don't know why or if you smoke and develop a persistent cough, see your healthcare provider. It's especially important to see your provider if your cough brings up blood or sputum, keeps you awake at night or affects your work or school performance. They can find the root cause of your cough and recommend a treatment plan. Follow your care plan as directed by your provider so you can stop coughing and feel better.

Clinically reviewed and updated April 2023.