Cough

Coughing is an important way to keep your throat and airways clear. But too much coughing may mean you have a disease or disorder.

Some coughs are dry. Others are productive. A productive cough is one that brings up mucus. Mucus is also called phlegm or sputum.

Coughs can be either acute or chronic:

• Acute coughs usually begin rapidly and are often due to a cold, flu, or sinus infection. They usually go away after 3 weeks.
• Subacute coughs last 3 to 8 weeks and often much sooner than that.
• Chronic coughs last longer than 8 weeks.

Common causes of coughing are:

• Allergies that involve the nose or sinuses
• Asthma and COPD (emphysema or chronic bronchitis)
• The common cold, flu, and other viral infections
• Lung infections such as pneumonia or acute bronchitis
• Sinusitis with postnasal drip
• Gastroesophageal reflux disease (GERD)

Other causes include:

• ACE inhibitors or less often ARB medicines used to treat high blood pressure, heart failure, or kidney diseases
• Cigarette smoking or exposure to secondhand smoke (or smoking other substances like marijuana)
• Lung cancer
• Lung disease such as bronchiectasis, cystic fibrosis, or interstitial lung disease
• Sometimes no specific cause is found

Call 911 or the local emergency number if you have:

• Shortness of breath or difficulty breathing
• Hives or a swollen face or throat with difficulty swallowing

Contact your provider right away if you have a cough and any of the following:

• Heart disease, swelling in your legs, or a cough that gets worse when you lie down (may be signs of heart failure)
• Have had contact with someone who has tuberculosis
• Unintentional weight loss or night sweats (could be tuberculosis)
• An infant younger than 3 months old who has a cough
• A cough that lasts longer than 10 to 14 days
• A cough that produces blood
• Fever (may be a sign of a bacterial infection that requires antibiotics)
• A high-pitched sound (called stridor) when breathing in
• Thick, foul-smelling, yellowish-green phlegm (could be a bacterial infection)
• A violent cough that begins rapidly

Your provider will perform a physical exam. You will be asked about your cough. Questions may include:

• When the cough began
• What it sounds like
• If there is a pattern to it
• What makes it better or worse
• If you have other symptoms, such as a fever

Your provider will examine your ears, nose, throat, and chest.

Tests that may be done include:

• Chest x-ray or CT scan
• Lung function tests
• Blood tests
• Tests to check the heart, such as an echocardiogram
• Gastroesophageal reflux evaluation tests (for example barium swallow)
• Swabs of the nose or throat to check for a virus infection
• CT scan of the sinuses

Treatment depends on the cause of the cough.

Chung KF, Mazzone SB. Cough. In: Broaddus VC, King TE, Ernst JD, et al, eds. Murray and Nadel's Textbook of Respiratory Medicine. 7th ed. Philadelphia, PA: Elsevier; 2022:chap 37.

Kraft M. Approach to the patient with respiratory disease. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 71.

Last reviewed on: 4/1/2025

Frank D. Brodkey, MD, FCCM, Associate Professor, Section of Pulmonary and Critical Care Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.