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Wheezing in Infants and Young Children


Rajeev Bhatia

, MD, Phoenix Children's Hospital

Reviewed/Revised Jan 2022 | Modified Sep 2022
Topic Resources

Wheezing is a relatively high-pitched whistling sound that occurs during breathing when the airways are partially blocked or narrowed.

  • Wheezing is caused by a narrowing of the airways.

  • Other symptoms depend on the cause and may include cough, fever, and runny nose.

  • The diagnosis of the cause is based on chest x-rays and sometimes other tests.

  • Treatment can include bronchodilators and corticosteroids.

Wheezing is caused by a narrowing or blockage (obstruction) of the airways. The narrowing can be caused by one or more of the following:

  • Swelling of the tissues in the airways

  • Spasm of the tiny muscles in the walls of the airways (bronchospasm)

  • Accumulation of mucus in the airways

Recurring episodes of wheezing are common in the first few years of life. Until recently, doctors diagnosed these episodes as asthma Asthma in Children Asthma is a recurring inflammatory lung disorder in which certain stimuli (triggers) inflame the airways and cause them to temporarily narrow, resulting in difficulty breathing. Asthma triggers... read more Asthma in Children because, like asthma, episodes could be relieved by inhaling drugs that open the airways (bronchodilators) and because most adults who have asthma first developed symptoms in childhood. Now, however, doctors know that only some infants and young children who have such episodes of wheezing have asthma in later childhood or adolescence.

Did You Know...

  • Not all wheezing is caused by asthma.

Children who are more likely to be eventually diagnosed with asthma include children who have one or more of the following risk factors:

However, in most children, wheezing episodes stop by 6 to 10 years of age, and doctors do not diagnose these children as having asthma. Such children have other causes for their recurring episodes of wheezing.


The most common cause of a single, sudden episode of wheezing in infants and young children is usually a

  • Viral respiratory infection

The most common causes of recurring episodes of wheezing are

Whatever the initial cause of the wheezing, symptoms are often worsened by allergies or inhaled irritants (such as tobacco smoke).


A high-pitched wheezing sound is heard when the child breathes out. If airway narrowing is severe, the wheezing sound can be heard when the child breathes in. Very ill children may also breathe rapidly, use a lot of their chest muscles to breathe, and have flaring of the nostrils and a bluish discoloration of the skin (cyanosis Cyanosis Cyanosis is a bluish or grayish discoloration of the skin resulting from an inadequate amount of oxygen in the blood. Cyanosis occurs when oxygen-depleted (deoxygenated) blood, which is bluish... read more ). Fever may be present in children with a lung infection.


  • Chest x-rays

  • Rarely swallowing studies, computed tomography, or bronchoscopy


  • For flare-ups, bronchodilators and sometimes corticosteroids

  • For severe wheezing, daily use of bronchodilators and anti-inflammatory drugs used for asthma

Infants and young children who have flare-ups of wheezing are given an inhaled bronchodilator (such as albuterol) and, if the wheezing is severe, corticosteroids (such as prednisone) given by mouth or vein.

Children who are unlikely to develop persistent asthma, such as children who do not have signs of allergies or a family history of allergies or asthma and whose episodes of wheezing are relatively mild and infrequent, usually require only inhaled bronchodilators used as needed to control their symptoms.

Most young children with more frequent and/or severe episodes of wheezing are helped by as-needed use of bronchodilators and by daily use of anti-inflammatory drugs that are used for asthma ( see Chronic asthma Chronic asthma Asthma is a recurring inflammatory lung disorder in which certain stimuli (triggers) inflame the airways and cause them to temporarily narrow, resulting in difficulty breathing. Asthma triggers... read more Chronic asthma ). Although daily use of a leukotriene modifier (such as montelukast or zafirlukast) or a low-dose inhaled corticosteroid (such as beclomethasone) decreases the severity and frequency of episodes of wheezing, these drugs do not change the way the disorder naturally progresses.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Accuneb, ProAir digihaler, Proair HFA, ProAir RespiClick, Proventil, Proventil HFA, Proventil Repetabs, Respirol , Ventolin, Ventolin HFA, Ventolin Syrup, Volmax, VoSpire ER
Deltasone, Predone, RAYOS, Sterapred, Sterapred DS
Beclovent, Beconase AQ, Qnasl, Qnasl Children's, QVAR, QVAR RediHaler, Vancenase, Vancenase AQ, Vanceril
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