Cough

Overview

Definition

A cough is a sudden burst of air from the lungs. It can help to clear secretions or foreign items 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

Causes

An acute cough is usually caused by an infection, such as a cold or the flu. In some cases, an acute cough can be the sign of other conditions, such as:

  • Exposure to an irritant or an allergen
  • Aspiration of (inhaled) a foreign body
  • Acute bronchitis
  • Pneumonia

Subacute cough is often a cough that comes after a respiratory infection like a cold or flu. It can also happen after breathing in things that irritate your airways.

A chronic cough has many causes. Common examples include:

  • Chronic obstructive pulmonary disease (COPD), which includes chronic bronchitis or emphysema
  • Cough variant asthma
  • Acid reflux from the stomach into the esophagus—gastroesophageal reflux disease (GERD)
  • Postnasal drip, which may be due to:
    • Inhaling irritants often
    • Sinus inflammation
    • Allergies
  • Bronchiectasis
  • Certain medications, such as ACE inhibitors
Alveoli (Air Sacs) of Lung
Chronic Bronchitis
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Risk Factors

Factors that may increase your risk of developing a cough include:

  • Infection
  • Tobacco smoke
  • Harmful fumes
  • Allergens, such as pollen and dust
  • Smog and other environmental pollutants

Smoking is a major risk factor for serious conditions linked to chronic cough. Most common include lung cancer and COPD.

SymptomsandDiagnosis

Symptoms

Coughs can have fluid or be dry. You may find that your cough is worse when waking up and at the night when you are 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 fluid that you cough up from your airways

When Should I Call for Medical Help Immediately?

Call for medical help or go to the emergency room right away if you have cough with:

  • Pink or frothy sputum
  • Trouble breathing
  • Chest pain
  • Rapid heartbeat

Diagnosis

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:

  • Chest x-ray
  • CT scan

During a bronchoscopy, a lighted tube with a camera is inserted into the lungs. Tissue samples can also be taken to be closely examined.

Your lung function and capacity may be tested. This can be done with pulmonary function tests or a methacholine challenge test.

Treatments

Treatment

The best treatment for a cough is to treat the underlying condition.

Medication

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.

Lifestyle Changes

Consider putting a steam vaporizer or cool-mist humidifier in your room. This type of moisture therapy may help to make secretions looser and easier to cough up.

Prevention

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.
  • 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.

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Edits to original content made by Denver Health.

RESOURCES

American Lung Association http://www.lung.org 

Family Doctor—American Academy of Family Physicians https://www.familydoctor.org 

CANADIAN RESOURCES

Health Canada http://www.hc-sc.gc.ca 

The Lung Association https://www.lung.ca 

References

Chronic cough in adults. EBSCO DynaMed Plus website. Available at:  http://www.dynamed.com/topics/dmp~AN~T146529/Chronic-cough-in-adults . Updated May 25, 2017. Accessed August 14, 2017.

Cough. Family Doctor—American Academy of Family Physicians website. Available at: https://familydoctor.org/symptom/cough. Accessed August 14, 2017.

Coughlin L. Cough: Diagnosis and management. Am Fam Physician. 2007;75(4):567-575.