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Croup is a common childhood ailment. Typically, it arises from a viral infection of the larynx (voice box) and is associated with mild upper respiratory symptoms such as a runny nose and cough. The key symptom is a harsh barking cough. Croup is usually not serious and most children recover within a few days. In a small percentage of cases, a child develops breathing difficulties and may need medical attention.


At one time, the term croup was primarily associated with diphtheria, a life-threatening respiratory infection. Owing to widespread vaccinations, diphtheria has become rare in the United States, and croup currently refers to a mild viral infection of the larynx. Croup is also known as laryngotracheitis, a medical term that describes the inflammation of the trachea (windpipe) and larynx.
Parainfluenza viruses are the typical root cause of the infection, but influenza (flu) and cold viruses may sometimes be responsible. All of these viruses are highly contagious and easily transmitted between individuals via sneezing and coughing. Children between the ages of three months and six years are usually affected, with the greatest incidence at one to two years of age. Croup can occur at any time of the year, but it is most typical during early autumn and winter. The characteristic harsh barking of a croupy cough can be very distressing, but it rarely indicates a serious problem. Most children with croup can be treated very effectively at home; however, 1-5% may require medical treatment.
Croup may sometimes be confused with more serious conditions, such as epiglottitis or bacterial tracheitis. These ailments arise from bacterial infection and must receive medical treatment.

Causes and symptoms

The larynx and trachea may become inflamed or swollen from an upper respiratory viral infection. The hallmark sign of croup is a harsh, barking cough. This cough may be preceded by one to three days of symptoms that resemble a slight cold. A croupy cough is often accompanied by a runny nose, hoarseness, and a low fever. When the child inhales, there may be a raspy or high-pitched noise, called stridor, owing to the narrowed airway and accumulated mucus. In the presence of stridor, medical attention is required.
However, the airway rarely narrows so much that breathing is impeded. Symptoms usually go away completely within a few days. Medical treatment may be sought if the child's symptoms do not respond to home treatment.
Emergency medical treatment is required immediately if the child has difficulty breathing, swallowing, or talking; develops a high fever (103°F/39.4°C or more); seems unalert or confused; or has pale or blue-tinged skin.


Croup is diagnosed based on the symptoms. If symptoms are particularly severe, or do not respond to treatment, an x ray of the throat area is done to assess the possibility of epiglottitis or other blockage of the airway.


Home treatment is the usual method of managing croup symptoms. It is important that the child is kept comfortable and calm to the best degree possible, because crying can make symptoms seem worse. Humid air can help a child with croup feel more comfortable. Recommended methods include sitting in a steamy bathroom with the hot water running or using a cool-water vaporizer or humidifier. However, research in 2004 found that although cool-mist therapy at home or in the hospital may add to the child's comfort, it does little to treat the actual condition. The child should drink frequently in order to stay well hydrated. To treat any fever, the child may be given an appropriate dose of acetaminophen (like Tylenol). Antihistamines and decongestants are ineffective in treating croup. All children under the age of 18 should not be given aspirin, as it may cause Reye's syndrome, a life-threatening disease of the brain.
If the child does not respond to home treatment, medical treatment at a doctor's office or an emergency room could be necessary. Based on the severity of symptoms and the response to treatment, the child may need to be admitted to a hospital.
For immediate symptom relief, epinephrine may be administered as an inhaled aerosol. Effects last for up to two hours, but there is a possibility that symptoms may return. For that reason, the child is kept under supervision for three or more hours. Steroids (corticosteroids) such as prednisone may be used to treat croup, particularly if the child has stridor when resting.
Of the 1-5% of children requiring medical treatment, approximately 1% need respiratory support. Such support involves intubation (inserting a tube into the trachea) and oxygen administration.

Alternative treatment

Botanical/herbal medicines can be helpful in healing the cough that is commonly associated with croup. Several herbs to consider for cough treatment include aniseed (Pimpinella anisum), sundew (Drosera rotundifolia), thyme (Thymus vulgaris), and wild cherry bark (Prunus serotina). Homeopathic medicine can be very effective in treating cases of croup. Choosing the correct remedy (a common choice is aconite or monkshood, Aconitum napellus) is always the key to the success of this type of treatment.


Croup is a temporary condition and children typically recover completely within three to six days. Children can experience one or more episodes of croup during early childhood; however, croup is rarely a dangerous condition.


Croup is caused by highly transmissible viruses and is often difficult to impossible to prevent.



Kirn, Timothy F. "Cool Mist Therapy is Losing Credibility for Croup: Steroids or Even Epinephrine May Be Needed." Pediatric News March 2004: 10-11.

Key terms

Diphtheria — A serious, frequently fatal, bacterial infection that affects the respiratory tract. Vaccinations given in childhood have made diphtheria very rare in the United States.
Epiglottitis — A bacterial infection that affects the epiglottis. The epiglottis is a flap of tissue that prevents food and fluid from entering the trachea. The infection causes it to become swollen, potentially blocking the airway. Other symptoms include a high fever, nonbarking cough, muffled voice, and an inability to swallow properly (possibly indicated by drooling).
Glucocorticoid — A hormone that helps in digestion of carbohydrates and reduces inflammation.
Larynx — Commonly called the voice box, it is the area of the trachea that contains the vocal cords.
Stridor — The medical term used to describe the high-pitched or rasping noise made when air is inhaled.
Trachea — Commonly called the windpipe, it is the air pathway that connects the nose and mouth to the lungs.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.


a condition resulting from acute partial obstruction of the upper airway, seen mainly in infants and young children; characteristics include resonant barking cough, hoarseness, and persistent stridor. It may be caused by a viral infection (usually a parainfluenzavirus), a bacterial infection (usually Staphylococcus aureus, Streptococcus pneumoniae, or Streptococcus pyogenes,) an allergy, a foreign body, or a tumor.
bacterial croup (membranous croup) (pseudomembranous croup) bacterial tracheitis.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


1. Acute obstruction of upper airway in infants and children characterized by a barking cough with difficult and noisy respiration.
2. Laryngotracheobronchitis in infants and young children caused by parainfluenza viruses 1 and 2.
3. An anatomic term in veterinary medicine referring to the topline located between the base of the tail and forward to the cranial aspect of the wings of the ilium in dogs and horses.
[Scots, probably from A.S. kropan, to cry aloud]
Farlex Partner Medical Dictionary © Farlex 2012

croup 1

A pathological condition of the larynx, especially in infants and children, that is characterized by respiratory difficulty and a hoarse, brassy cough.

croup′ous (kro͞o′pəs), croup′y adj.

croup 2

The rump of a beast of burden, especially a horse.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


Acute laryngotracheobronchitis, angina trachealis, laryngostasis Pediatrics A heterogeneous group of acute infections, which cause upper-airway obstruction in children Epidemiology Annual incidence–3/100 children < 6 yrs–US; 1.3% require hospitalization Etiology Parainfluenza type 1, less often type 2 and 3, RSV, influenza virus, rubeola, adenovirus, Mycoplasma pneumoniae Clinical Brassy, seal-like barking or 'croupy' cough accompanied by inspiratory stridor and hoarseness, 2º to intense edema, laryngeal mucus, subglottic stenosis, progressive or episodic dyspnea, tachypnea, cyanosis, sternal and intercostal retractions, dysphagia, low-grade fever, chills, recent URI, ↓ breath sounds, restlessness DiffDx Angioneurotic edema, bacterial tracheitis, epiglottitis, foreign body aspiration, retropharyngeal abscess Management Dexamethasone, prednisolone, budesonide–nebulizer–effective for croup, mist tents, vaporizers, antibiotics, decongestants, cough suppressants, pain medication, fluids, nebulized racemic epinephrine; hospitalization if stridor
at rest
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


1. Laryngotracheobronchitis in infants and young children caused by parainfluenza viruses 1 and 2.
2. Any infection of the larynx in children, characterized by difficult and noisy respiration and a hoarse cough.
[Scots, probably from A.S. kropan, to cry aloud]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


Inflammation and swelling of the main air tubes to the lungs (laryngotracheobronchitis) affecting young children and causing difficult, harsh, noisy and painful breathing and a typical ‘barking’ cough.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

Patient discussion about croup

Q. Is this croup? My one year old son has a terrible cough. Each time he coughs its load and long. I am very worried. Is this croup and if so how is it treated?

A. Here is a video that explains about croup and how to treat it:

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