Croup (KROOP) is the name for a group of conditions, typically occurring in children, in which the trachea (windpipe) and larynx (voice box) become inflamed, and the upper airway narrows. As a result, croup can sometimes make breathing difficult. The characteristic symptom is a barking cough, which may be accompanied by a grunting or wheezing noise when the child inhales. Although the breathing difficulties frequently cause considerable alarm among parents, most children recover from croup without any complications.

What Is Croup?

Croup is an inflammation of the throat, and specifically the trachea * and the larynx * . The upper airway narrows, which may cause breathing difficulties. Typically occurring in childhood, the condition is characterized by a barking cough that often becomes especially evident when a child is crying. In more severe cases of croup, a high-pitched or squeaking noise called stridor * can be heard when the child takes a breath. The symptoms can appear suddenly or develop over a few days. Common cold symptoms, such as a runny nose, usually precede the onset of the barking cough. An allergy or a bacterial infection can produce symptoms of croup, but the majority of cases, 75 percent or more, are caused by a virus, usually parainfluenza * virus. Influenza viruses, adenovirus * , respiratory syncytial virus * , and measles virus also can cause croup.

Who Gets Croup?

Croup tends to develop in infants and toddlers, because the windpipe is still small enough to be impeded by swelling. As a child grows older, the risk of croup drops. Adult cases of croup, although very rare, do occur. Croup is most common during the winter months and in the early spring. In the same way that an adult with a cold might have laryngitis * , a child with a cold might get croup. In fact, many of the viruses that cause croup in children can lead to laryngitis in adults. Some children are more prone to croup, such as those who are born prematurely or who have narrowed upper airways. These children may get symptoms of croup every time they have a respiratory illness. Although the viruses that cause croup can pass easily between children through respiratory secretions, most children who come into contact with those viruses will not get croup.

What Are the Symptoms and Complications of Croup?

Croup is typically divided into two types: a spasmodic form and a viral form. Spasmodic croup results from an allergy or a mild respiratory infection and usually comes on suddenly. Viral croup arises from a viral infection and usually develops slowly over several days. A low fever is common in children with viral croup, but not among those with spasmodic croup. In both cases, children typically have a cough that resembles the sound of a barking seal. Crying can make the breathing symptoms worse. The symptoms also tend to worsen at night when children are tired, and a child with croup will often have trouble sleeping or even resting. In severe cases, when the airway becomes more swollen and narrowed, a child might experience difficulty breathing, which may include fast breathing and/or stridor. If oxygen intake drops too low, the lips, tongue, and skin around the mouth can start to appear bluish. In general, croup symptoms peak two to three days after they start, and the illness generally lasts less than a week. Children usually make a full recovery without complications, but in a small number of cases, they may experience an ear infection or pneumonia.

How Is Croup Diagnosed and Treated?

A barking cough is a telltale sign of croup. Other clues to the diagnosis are stridor, low fever (in cases of viral croup), common cold symptoms, previous bouts of croup, or a history of intubation * or other upper-airway problems. The degree of obstruction of the airways is the doctor's most important consideration in diagnosing and treating croup. If the bronchi (breathing tubes), the lungs, or the epiglottis * become infected, a child may be unable to breathe or swallow adequately, and that is a true medical emergency. If the symptoms are severe, or if the child does not respond quickly to treatment, medical professionals may recommend a neck x-ray to check for specific causes of the breathing difficulty.

For most cases of croup, however, parents can treat their children at home. A common home treatment for mild cases of croup is moist air from a steam-filled bathroom or a cool-mist humidifier. The mist moistens the child's airway, helps open the air passage, and relieves coughing. Parents may also find that taking the child outdoors for a few minutes, even in the winter, can ease a coughing attack quickly, because the cool air can shrink the swollen tissues lining the airway. As with most illnesses, drinking fluids and getting plenty of rest help the body heal. Cigarette smoke near a child with croup or any other respiratory illness can make symptoms worse. Doctors advise prompt medical treatment for serious croup infections. Treatment may include inhaled medications, including epinephrine * , to minimize swelling in the upper airways. Doctors often will administer corticosteroid * medicines to ease airway swelling for a few days while the child recovers from the virus infection that causes croup. As of 2015, croup was not preventable, but frequently washing hands and avoiding contact with people who have respiratory infections was known to lessen the chance of spreading the viruses that cause croup.

See also Common Cold • Epiglottitis • Influenza • Laryngitis • Pneumonia • Whooping Cough (Pertussis)


Books and Articles

Johnson, Christopher M. Keeping Your Kids out of the Emergency Room: A Guide to Childhood Injuries and Illnesses. Summit, PA: Rowman & Littlefield, 2013.


MedlinePlus. “Croup.” U.S. National Library of Medicine. (accessed December 1, 2015).


Centers for Disease Control and Prevention. 1600 Clifton Rd., Atlanta, GA 30333. Toll-free: 800-311-3435. Website: (accessed December 1, 2015).

Healthy Children/American Academy of Pediatrics. 141 Northwest Point Blvd., Elk Grove Village, IL 60007-1098. Telephone: 847-434-4000. Website: (accessed December 1, 2015).

* trachea (TRAY-kee-uh) is the windpipe—the firm, tubular structure that carries air from the throat to the lungs.

* larynx (LAIR-inks) is the voice box (which contains the vocal cords) and is located between the base of the tongue and the top of the windpipe.

* stridor (STRY-dor) is a highpitched, squeaking noise that occurs while breathing in, usually present only if there is narrowing or blockage of the upper airway.

* parainfluenza (pair-uh-in-floo- EN-zuh) is a family of viruses that cause respiratory infections.

* adenovirus (ah-deh-no-VY-rus) is a type of virus that can produce a variety of symptoms, including upper respiratory disease, when it infects humans.

* respiratory syncytial virus (RESpuh- ruh-tor-e sin-SIH-she-ul), or RSV, is a virus that infects the respiratory tract and typically causes minor symptoms in adults but can lead to more serious respiratory illnesses in children.

* laryngitis (lair-in-JY-tis) is an inflammation of the vocal cords that causes hoarseness or a temporary loss of voice.

* intubation (in-too-BAY-shun) is the insertion of a tube into the windpipe to allow air and gases to flow into and out of the lungs in a person who needs help breathing.

* epiglottis (eh-pih-GLAH-tis) is a soft flap of tissue that covers the opening of the trachea (windpipe) when a person swallows to prevent food or fluid from entering the airway and lungs.

* epinephrine (eh-pih-NEH-frin) is a chemical substance produced by the body that can also be given as a medication to constrict, or narrow, small blood vessels, stimulate the heart, and cause other effects, such as helping to open narrowed airways in conditions like asthma and croup.

* corticosteroid (KOR-ti-ko-STERoid) is one of several medications that are prescribed to reduce inflammation and sometimes to suppress the body's immune response.

Disclaimer:   This information is not a tool for self-diagnosis or a substitute for professional care.

(MLA 8th Edition)