A cough is a sudden expulsion of air from the lungs. Its purpose is usually to clear secretions and inhaled foreign substances from the lungs and respiratory tract.
There are different types of cough:
- Acute cough—lasts for less than 3 weeks
- Subacute cough—lasts 3-8 weeks
- Chronic cough—lasts longer than 8 weeks
Subacute cough is often a cough that follows a respiratory infection. It can also be caused by exposure to irritants or to anything that can cause chronic cough.
A chronic cough has many causes. Common examples include:
- Chronic obstructive pulmonary disease (COPD), which includes chronic bronchitis or emphysema
- Acid reflux from the stomach into the esophagus—gastroesophageal reflux disease (GERD)
Postnasal drip, which may be due to:
- Repeated inhalation of environmental irritants
- Sinus inflammation
- Certain medications, such as ACE inhibitors
Alveoli (Air Sacs) of Lung
Factors that may increase your risk of developing a cough include:
- Tobacco smoke
- Harmful fumes
- Allergens, such as pollen and dust
- Smog and other environmental pollutants
A cough can be a symptom of an underlying condition.
Coughs can be productive or dry. You may find that your cough is worse when waking up and during the night while lying down.
When Should I Call My Doctor?
Call your doctor if you have:
- Acute cough that worsens or does not go away on its own
- Cough lasting more than 8 weeks
- Signs of an infection, including fever and chills
- Cough with wheezing
- Blood in the sputum
You will be asked about your symptoms and medical history. A physical exam will be done.
Acute cough is usually diagnosed by its accompanying symptoms.
Your bodily fluids may be tested. This can be done with:
- Blood tests
- Skin tests
- Analysis of a sputum sample
Images may be taken of your bodily structures. This can be done with:
Your lung function and capacity may be tested. This can be done with pulmonary function tests.
The best treatment for a cough is to treat the underlying condition.
There are many over-the-counter (OTC) cough and cold products available. These include decongestants, expectorants, antihistamines, and antitussives.
Note: Cough and cold medications should not be used in children under 2 years old, and they are not recommended in children under 4 years old. The US Food and Drug Administration has not completed its review regarding the safety of over-the-counter cough and cold medications in children ages 2-11 years. Rare, but serious side effects have been reported.
To reduce your chances of developing a cough:
- If you smoke, talk to your doctor about strategies to quit. Smoking affects your lung function and increases your risk of many diseases.
- Get proper treatment for the underlying condition.
When working in areas where harmful fumes or airborne substances are present:
- Be sure the area is properly ventilated.
- Wear a protective mask or respirator.
American Lung Association
Family Doctor—American Academy of Family Physicians
Chronic cough in adults. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T146529/Chronic-cough-in-adults. Updated November 18, 2015. Accessed September 23, 2016.
Cough. American Academy of Family Physicians Family Doctor website. Available at: http://familydoctor.org/familydoctor/en/health-tools/search-by-symptom/cough.html. Accessed September 17, 2014.
Coughlin L. Cough: Diagnosis and management. Am Fam Physician. 2007;75(4):567-575.
1/30/2008 DynaMed Plus Systematic Literature Surveillance http://www.dynamed.com/topics/dmp~AN~T146529/Chronic-cough-in-adults: Public health advisory: Nonprescription cough and cold medicine use in children—FDA recommends that over-the-counter (OTC) cough and cold products not be used for infants and children under 2 years of age. US Food and Drug Administration website. Available at: http://www.fda.gov/ForConsumers/ConsumerUpdates/ucm051137.htm. Updated August 20, 2013. Accessed September 17, 2014.
1/30/2008 DynaMed Plus Systematic Literature Surveillance http://www.dynamed.com/topics/dmp~AN~T146529/Chronic-cough-in-adults: Paul IM, Beiler J, McMonagle A, Shaffer ML, Duda L, Berlin CM Jr. Effect of honey, dextromethorphan, and no treatment on nocturnal cough and sleep quality for coughing children and their parents. Arch Pediatr Adolesc Med. 2007;161(6):1149-1153.
11/12/2010 DynaMed's Systematic Literature Surveillance http://www.dynamed.com/topics/dmp~AN~T146529/Chronic-cough-in-adults: Smith S, Schroeder K, Fahey T. Over-the-counter (OTC) medications for acute cough in children and adults in ambulatory settings. Cochrane Database Syst Rev. 2010;(9):CD001831.
Last reviewed August 2015 by David Horn, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.