What causes shortness of breath?

Shortness of breath is a common symptom of allergy, infection, inflammation, injury, or certain metabolic conditions. Shortness of breath may occur in various conditions affecting the lungs or entire pulmonary system, or in association with more generalized conditions, such as hypotension (low blood pressure) or obesity.

Asthma reactions triggered by allergies lead to shortness of breath, and in severe cases, such reactions can be life threatening. The majority of lung diseases result in shortness of breath. In rare cases, shortness of breath may be a symptom of serious lung or bronchial tube infections, such as pneumonia or bronchiolitis in young children. Certain heart conditions, such as congestive cardiac failure, may be accompanied by shortness of breath. Shortness of breath can also be a sign of lung cancer, particularly when accompanied by hemoptysis (coughing up blood).

Respiratory causes of shortness of breath

Shortness of breath may be caused by respiratory conditions including:

  • Asthma and allergies
  • Bronchiolitis (inflammation of the small airways known as bronchioles) or bronchitis
  • Bronchiectasis (dilation of the airways)
  • Chronic obstructive pulmonary disease (COPD; includes emphysema and chronic bronchitis)
  • Empyema (accumulation of pus around the lungs)
  • Hemothorax (blood in the lung)
  • Lung cancer
  • Pneumonia
  • Pneumothorax (collapsed lung)
  • Pulmonary embolism (blockage of a pulmonary artery due to a blood clot)
  • Pulmonary hypertension (high blood pressure in the arteries of the lungs)
  • Tuberculosis (serious infection affecting the lungs and other organs)

Cardiovascular causes of shortness of breath

Shortness of breath can also be caused by cardiovascular disorders including:

  • Cardiogenic shock (shock caused by heart damage and ineffective heart function)
  • Cardiomyopathy (weakened or abnormal heart muscle and function)
  • Cardiovascular disease (due to atherosclerosis, or hardening of the arteries, or other causes)
  • Congenital heart defects
  • Congestive heart failure (deterioration of the heart’s ability to pump blood)
  • Myocardial infarction (heart attack)

Other causes of shortness of breath

Shortness of breath can also have other causes including:

  • Anemia
  • Dehydration (loss of body fluids and electrolytes, which can be life threatening when severe and untreated)
  • Diabetic ketoacidosis (life-threatening complication of diabetes)
  • Electrolyte imbalance
  • Kidney or liver failure
  • Sepsis (life-threatening bacterial blood infection)

Serious or life-threatening causes of shortness of breath

In some cases, shortness of breath may be a symptom of a serious or life-threatening condition that should be immediately evaluated in an emergency setting. These include:

  • Anaphylaxis (severe allergic reaction)
  • Cardiogenic shock (shock caused by heart damage and ineffective heart function)
  • Dehydration (loss of body fluids and electrolytes, which can be life threatening when severe and untreated)
  • Diabetic ketoacidosis (life-threatening complication of diabetes)
  • Pneumonia
  • Pulmonary embolism (blockage of a pulmonary artery due to a blood clot)
  • Sepsis (life-threatening bacterial blood infection)

Questions for diagnosing the cause of shortness of breath

In order to diagnose your condition, your health care provider will ask you a series of questions related to your shortness of breath including:

  • How long have you felt shortness of breath?
  • Do you have any other symptoms?
  • What medications are you taking?
  • Do any particular activities cause you to feel shortness of breath?

What are the potential complications of shortness of breath?

It is vital to seek prompt treatment if you experience shortness of breath as it can be a sign of a serious disease and, left untreated, may put you at risk of serious complications and even permanent damage. Once your doctor has diagnosed the underlying cause, you should make every effort to follow the recommended treatment plan precisely in order to minimize risk of potential complications including:

  • Brain damage
  • Heart failure
  • Respiratory failure
  • Spread of cancer
  • Spread of infection

References:

Shortness of breath. FamilyDoctor.org. http://familydoctor.org/online/famdocen/home/tools/symptom/521.html. Accessed May 31, 2011.

Breathing difficulty. Medline Plus, a service of the National Library of Medicine National Institutes of Health. http://www.nlm.nih.gov/medlineplus/ency/article/003075.htm. Accessed May 31, 2011.

INTRODUCTION

What is shortness of breath?

Shortness of breath is a common symptom of allergy, infection, inflammation, injury, or certain metabolic conditions. Shortness of breath results when a signal from the brain causes the lungs to increase breathing frequency. You may also experience shortness of breath because of conditions affecting the lungs or entire pulmonary system, or in association with more generalized conditions, such a... Read more about shortness of breathintroduction

SYMPTOMS

What other symptoms might occur with shortness of breath?

Shortness of breath may accompany other symptoms, which can vary depending on the underlying disease, disorder or condition. Symptoms known to commonly affect the respiratory system may also involve other body systems.

Respiratory symptoms that may occur along with shortness of breath

Shortness of breath may accompany other symptoms affecting the respiratory system incl... Read more about shortness of breathsymptoms

Medical Reviewer: All content has been reviewed by board-certified physicians under the direction of Rich Klasco, M.D., FACEP. Last Annual Review Date: May 2, 2011 Copyright: © Copyright 2011 Health Grades, Inc. All rights reserved. May not be reproduced or reprinted without permission from Health Grades, Inc. Use of this information is governed by the HealthGrades User Agreement.

This Article is Filed Under: Lungs, Breathing and Respiration


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