What causes Croup?

Croup is most often caused by a virus with Parainfluenza virus being the most common. It is for the most part similar to cold viruses your child will encounter except it causes some atypical swelling in their upper airway (trachea).

What are the symptoms of croup?

Your child may start with a low grade fever and cough followed by hoarseness, barky cough, and stridor (a coarse, raspy, musical sound when they take a breath in which can mimic wheezing). These symptoms happen because the virus causes inflammation, or swelling, in the upper airway.  Stridor may only be heard when the child is upset or crying.  Symptoms often come on suddenly and typically happen in the middle of the night.  Usually nights 2-3 are the worst, but symptoms can last about a week.

How is it treated?

Because it is caused by a virus, antibiotics do not help.

For patients with severe symptoms, the doctor may give a one-time dose of oral steroids in the office to reduce upper airway swelling making it more comfortable for your child to breathe. Try to keep your child calm/happy.

You can also try to make your child more comfortable by having them breathe in moist air (cool mist humidifiers, a steamy shower, or the cold air standing in front of an open freezer), but studies have not shown these to necessarily help.

When should I call the doctor?

  1. Your child has stridor and discomfort when resting/calm for more than 30 minutes.
  2. Your child is breathing fast (breathing faster than 50-60 times per minute depending on your child’s age), or working harder to breathe (the skin between the ribs is being pulled in with each breath or they are not able to talk to you in full sentences because they are working so hard).
  3. Your child is not able to drink enough fluids to have urine output at least once every 8 hours.
  4. Your child has a temperature >101F for >72 hours. (This is not dangerous but if you have not already seen the doctor, come in for an evaluation).
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