Croup is a viral infection, most often parainfluenza, that swells the larynx and trachea in children from about 6 months to 3 years old. Most cases are mild and are handled in clinic with a single dose of steroid and clear advice for the family.
Key symptoms
- Barking, seal-like cough, worse at night
- Hoarse voice
- Noisy breathing on inspiration (stridor), often when crying
- Runny nose and low fever a day or two before
What you find on exam
- Stridor at rest or only when the child is upset
- Work of breathing: retractions, nasal flaring
- Oxygen saturation, usually normal in mild croup
- Alertness, color and hydration
- No drooling or toxic look; if present, think of epiglottitis
Tests
- Diagnosis is clinical; no tests needed in typical cases
- Severity score such as the Westley croup score
- Neck X-ray only if the picture is atypical (steeple sign)
Treatment basics
- Single dose of oral dexamethasone (0.15 to 0.6 mg/kg) for all severities
- Nebulized epinephrine for stridor at rest, then observe for 2 to 4 hours
- Keep the child calm on a parent's lap; avoid upsetting procedures
- Fever control and fluids at home
- Teach parents when to come back or call 911
Red flags
- Stridor at rest or severe retractions
- Drooling, trouble swallowing or a toxic look
- Low oxygen, cyanosis, exhaustion or decreased alertness
Practice it in Making Synapses
Making Synapses cases
Related guides
Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; NCSBN 2026 NCLEX-RN Test Plan. Written by Making Synapses. Making Synapses is not affiliated with these organizations.