Overview of Wheezing Breaths

Wheezing is a high-pitched whistling sound that can occur with certain lung and medical conditions when you breathe. It is common, and sometimes wheezing is a sign of a medical emergency. You can have wheezing without other symptoms, or you can also have other symptoms, such as shortness of breath. There are many possible causes, such as asthma and allergies. You need to have an accurate diagnosis of the cause of your wheezing so you can get effective treatment.

woman wheezing
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Definition

Wheezing can occur with inspiration (breathing in) and with expiration (breathing out), though expiratory wheezing is more common. Most people think of asthma when they hear wheezing, but other causes need to be considered too.

Sometimes people have more than one condition which leads to wheezing.

Auscultation

It's important to know whether the sounds you hear in your lung are truly wheezing. Why? Because there are other sounds that can be mistaken for wheezing.

During your physical examination, your healthcare professionals will auscultate (listen to) your lungs for sounds as you breathe.

Your lungs may sound normal with auscultation, with a quiet sound of air flowing in and out, or you can have sounds that indicate a medical problem—such as wheezing crackles, or stridor.

It's important to distinguish wheezing from stridor, another serious symptom that often has a different pitch and is caused by different conditions. Both types of sounds can be signs of life-threatening medical emergencies.

Wheezing vs. Stridor

Wheezing is often a medium-pitched sound that is loudest during expiration. It has a fairly continuous musical sound including more than one note.

The sound of wheezing is created by a narrowing of the airways. This can be due to swelling or blockage anywhere from the throat down to the smallest airways.

You can mistake stridor for wheezing.

Some differences between the two:

  • Stridor has a sound that is usually monophonic—meaning that only one note is heard rather than a variety of musical notes.
  • Stridor tends to be higher in pitch than wheezing.
  • Stridor occurs predominately during inspiration.
  • Stridor is usually loudest over the front of the neck, whereas wheezing can be loudest over the lungs.

Causes

The most common causes of wheezing are asthma and chronic obstructive pulmonary disease (COPD), but there are many potential causes including:

  • Anaphylaxis: This medical emergency is a severe allergic reaction (often due to a bee sting, medications, or eating nuts or shellfish) that causes swelling in the throat.
  • Bronchitis: This can be acute (lasting only a few days) or chronic (lasting weeks to months to years).
  • Bronchiolitis: This is an infection that involves the bronchioles (the smallest airways) and is most common in children. It is often caused by respiratory syncytial virus (RSV).
  • Inhaling (aspirating) a foreign body: Choking can sometimes cause wheezing if an inhaled object does not completely obstruct the airways. Wheezing related to foreign body inhalation is usually localized to one side of the chest.
  • Pneumonia
  • Bronchiectasis: Widening of the airways, often due to childhood infections or cystic fibrosis, is another cause of wheezing. While cystic fibrosis is most commonly diagnosed in early childhood, it is sometimes diagnosed in adulthood.
  • Viral infections: Many viral infections can cause wheezing, especially in children.
  • Lung cancer: Obstruction of the airway by a tumor can lead to a wheezing sound.
  • Heart failure: This can cause fluid to back up in the lungs.
  • Pulmonary embolism: Blood clots in the legs may break off and travel to the lungs, very rarely causing wheezing.
  • Acid reflux: It may not seem obvious, but acid reflux is a fairly common cause of wheezing.
  • Hypersensitivity pneumonitis: Chronic inflammation of the lungs caused by such things as moldy hay and bird droppings may cause wheezing.
  • Medications (especially aspirin)
  • Vocal cord dysfunction: Caused by one or both of the vocal cords closing unintentionally during breathing. This is also known as “vocal cord asthma.”
  • Epiglottitis: A medical emergency marked by symptoms such as fever, drooling, and sitting in an upright position in an attempt to breathe, epiglottitis is caused by an infection of the epiglottis, a small piece of cartilage attached to the end of the tongue. Epiglottitis often causes stridor that is heard over the neck, but it may also result in wheezing.

Diagnosis

If you have been wheezing or have had a change in symptoms, it is important to see your healthcare professional—even if you have experienced wheezing in the past or have been diagnosed with asthma.

Call for emergency medical help if you are experiencing chest pains, lightheadedness, shortness of breath, have a bluish tint to your lips and skin, or swelling of your face, neck, or lips.

Evaluation

The first thing your practitioner will do is to make sure you are comfortable and stable. In an emergency, medical personnel and technicians begin with "ABD." This stands for airway, breathing, then circulation. It is important to assess these before going on to try to determine what is actually causing the wheezing.

Once you are stable, your medical team will talk to you about your medical history and perform a physical exam.

Some of the questions they may ask you include:

  • When did your symptoms begin?
  • Have you ever had symptoms like this before?
  • Have you choked while eating?
  • Have you been stung by a bee or have you eaten foods that may cause serious allergic reactions, such as shellfish or nuts?
  • Do you have any other symptoms, such as a cough, shortness of breath, chest pain, hives, swelling of your face or neck, or coughing up blood?
  • Is your wheezing worse at night or during the day?
  • Do you have a personal or family history of asthma, eczema, lung diseases, or lung cancer?
  • Do you, or have you ever, smoked?

Your physical examination will usually begin with measurements of your vital signs, oxygen level, and a lung and heart auscultation.

Testing

Tests to evaluate your wheezing and determine a cause will vary depending upon your history and physical examination.

Testing may include:

  • Chest X-ray
  • Spirometry
  • Blood tests, such as a white blood cell count to look for signs of infection
  • Pulmonary function tests
  • CT scan of your chest
  • Bronchoscopy if your healthcare provider is concerned that you may have aspirated (breathed in) a foreign object or that you may have a tumor in or near your airways
  • Laryngoscopy to look at your larynx and vocal cords
  • Allergy testing if your practitioner feels that you have allergies that are causing your airways to spasm

Treatment

Depending on how serious your symptoms are, your healthcare provider will first do what is necessary to make you comfortable and control your symptoms. Since there are many possible causes of wheezing, further treatment will depend on the cause of your wheezing.

The first steps are to ensure you are getting adequate oxygen into your lungs. Oxygen therapy is commonly used. If wheezing is caused by an allergic reaction, injectable epinephrine is often given.

Other treatments will depend upon the underlying causes of wheezing. For example, treatments for asthma will be used to open the airways, whereas a procedure such as a bronchoscopy may be recommended if it's thought that a foreign body could be blocking the airways.

A Word From Verywell

There are many causes of wheezing. An asthma attack can be life-threatening. Treatments have advanced significantly for asthma in the last decades, and many people are able to live relatively normal lives despite their disease. In the case of a life-threatening asthma attack called status asthmatics, intravenous medications, intubation and extracorporeal membrane oxygenation (ECMO) may be needed.

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6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. MedlinePlus. Wheezing. Updated May 20, 2018.

  2. Sarkar M, Madabhavi I, Niranjan N, Dogra M. Auscultation of the respiratory system. Annals of Thoracic Medicine. 2015;10(3):158-68. doi:10.4103/1817-1737.160831

  3. Irwin R. Evaluation of wheezing illnesses other than asthma in adults. UpToDate. Updated September 19, 2018.

  4. Ramos MB, Botana-Rial M, Garcia-Fontan E, Fernandez-Villar A, Torreira MG. Update in the extraction of airway foreign bodies in adultsJournal of Thoracic Disease. 2016;8(11):3452–3456. doi:10.21037/jtd.2016.11.32

  5. Celmina M, Paule S. Stridor in childrenBreathe (Sheff). 2018;14(3):e111–e117. doi:10.1183/20734735.017018

  6. American Academy of Allergy Asthma and Immunology. Asthma treatment and management.

Additional Reading
  • Harrison's Principles of Internal Medicine, 20th Edition. New York: McGraw Hill Education. 2019. Print.

  • Murray and Nadel's Textbook of Respiratory Medicine, 6th Edition. Elsevier. 2015.

  • Oo, S., and P. Le Souef. The wheezing child: an algorithm. Australian Family Physician. 2015. 44(6):360-4.