What are the signs of croup?

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Last updated: April 25, 2025View editorial policy

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From the Guidelines

Croup is a viral respiratory infection characterized by a barking cough, hoarseness, and stridor, with six key signs including a distinctive barking cough, stridor, hoarseness, respiratory distress, fever, and symptoms worsening at night. The treatment of croup depends on the severity of the condition, but it often includes a single dose of oral dexamethasone to reduce airway inflammation, as supported by recent studies 1.

Key Signs and Symptoms

  • A distinctive barking or "seal-like" cough
  • Stridor (especially when agitated or crying)
  • Hoarseness
  • Respiratory distress with retractions
  • Fever
  • Symptoms that typically worsen at night

Treatment

  • A single dose of oral dexamethasone (0.6 mg/kg, maximum 10 mg) to reduce airway inflammation
  • For moderate to severe cases, nebulized epinephrine (racemic epinephrine 2.25% solution, 0.5 mL in 2.5 mL normal saline) may be used in medical settings, although its effect is short-lived (1-2 hours) 1
  • Home management includes keeping the child calm, ensuring adequate hydration, using cool mist humidifiers, and sitting in a steamy bathroom

When to Seek Medical Attention

  • Significant breathing difficulty
  • Appears blue
  • Is excessively drowsy
  • Cannot drink fluids Most cases of croup resolve within 3-7 days, and the condition occurs because viruses cause inflammation and swelling of the larynx and trachea, narrowing the airway, particularly affecting children aged 6 months to 3 years whose airways are naturally smaller. The use of a clinical guideline and orderset can help reduce hospital admissions for croup, as shown in a recent study 1.

From the Research

Croup Signs and Symptoms

  • Croup is characterized by the abrupt onset of a barking cough, inspiratory stridor, hoarseness, and respiratory distress due to upper airway obstruction 2
  • The disease leads to signs of upper airway obstruction and must be differentiated from acute epiglottitis, bacterial tracheitis, or an inhaled foreign body 2
  • Croup affects about 3% of children per year, usually between the ages of 6 months and 3 years, and 75% of infections are caused by parainfluenza virus 2

Diagnosis and Assessment

  • The assessment of airway, breathing, and circulation, focusing on airway, is paramount in treating croup 3
  • Laboratory studies are seldom needed for diagnosis of croup, and viral cultures and rapid antigen testing have minimal impact on management 4
  • Radiography and laryngoscopy should be reserved for patients in whom alternative diagnoses are suspected 4

Treatment and Management

  • A single dose of oral, intramuscular, or intravenous dexamethasone improves symptoms and reduces return visits and length of hospitalization in children with croup of any severity 4
  • In patients with moderate to severe croup, the addition of nebulized epinephrine improves symptoms and reduces length of hospitalization 4
  • Corticosteroids, such as dexamethasone, and nebulized epinephrine are effective treatments for croup, with dexamethasone being more effective by clinical evaluation at 6 and 12 hours post-admission 5
  • The introduction of steroids in the treatment of croup has seen a significant reduction in hospital admissions and improved outcomes for children 3

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Croup.

BMJ clinical evidence, 2014

Research

Croup - assessment and management.

Australian family physician, 2010

Research

Croup: Diagnosis and Management.

American family physician, 2018

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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