Croup is a common childhood illness that affects the voice box (larynx) and windpipe (trachea). 

Children between 3 months and 5 years of age are most likely to get croup. Their airways are small, and any swelling can make it difficult to breathe. Most cases of croup are mild and last less than a week.

Croup is caused by viruses that are contagious. The viruses can spread through the air or by touching a contaminated surface. Less frequently, allergies may cause croup. Your baby can get croup at any time of year, but it is most common between October and March. 

What are signs and symptoms of croup?

Croup features a cough that sounds like a seal barking. Most children have what appears to be a mild cold for several days before the barking cough becomes evident. As the cough gets more frequent, the child may have labored breathing or stridor (a harsh, crowing noise made during inspiration).

Croup is typically much worse at night. It often lasts 5 or 6 nights, but the first night or two are usually the most severe. Rarely, croup can last for weeks. If croup lasts longer than a week or comes back often, contact your baby’s health provider. 

How is croup treated?

Most cases of croup can be safely managed at home, but call your health care provider for guidance, even in the middle of the night. Cool or moist air might bring relief. You might first try bringing the child into a steamy bathroom or outside into the cool night air. You can also try a cool-mist humidifier.

Your baby’s health provider may suggest acetaminophen to reduce your baby’s fever. Some babies also may need steroid medicines to relieve some symptoms. 

When should you call your baby's health provider?

Most croup can be safely managed at home with telephone support from your health care provider. Call 911 or your baby’s health provider right away if:

  • The croup is possibly being caused by an insect sting or inhaled object
  • Your baby has bluish lips or skin color
  • She is drooling
  • She has swallowing
  • Has stridor (noise when breathing in)
  • Has retractions (tugging-in between the ribs when breathing in)
  • Has trouble breathing
  • Is very irritable
  • Is not responding to home treatment

Do NOT wait until morning to address the problem.

Last reviewed: November, 2013