What is croup?

Croup is a respiratory infection that affects children, mainly during the fall and winter months. It affects children under age 5, and symptoms are most severe in children under age 3. Croup may last from 5 to 6 days, depending on the severity of the infection. It may have other complications, such as ear infection or pneumonia.

What causes croup?

Croup is most commonly caused by viruses such as influenza, parainfluenza, respiratory syncytial virus (RSV), measles, and adenovirus. This infection causes the upper airways to swell, making it difficult to breathe. Rarely, bacteria can complicate the viral infection and makes it more difficult to breathe.

What are the symptoms of croup?

  • A harsh or "barky" cough
  • Stridor (harsh, raspy vibrating sound when breathing in)
  • Difficulty breathing
  • Difficulty bending the neck
  • Fever, which may be high
  • Restlessness or nervousness at night or when it becomes harder to breathe

Last reviewed by a Cleveland Clinic medical professional on 09/17/2019.


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