What is the protocol for administering racemic epinephrine (adrenaline) in treating croup?

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Protocol for Administering Racemic Epinephrine in Croup

For treating croup, racemic epinephrine should be administered as a 2.25% inhalation solution at a dose of 0.05 mL/kg (maximum: 0.5 mL) in 2 mL of normal saline via nebulizer. 1 Many institutions standardize this to a 0.5 mL dose for all patients regardless of weight.

Dosing and Administration Details

Standard Dosing

  • Concentration: 2.25% racemic epinephrine inhalation solution
  • Dose calculation: 0.05 mL/kg up to maximum of 0.5 mL
  • Diluent: Mix with 2 mL of normal saline
  • Administration route: Nebulizer
  • Standard institutional dose: Many facilities use a standard 0.5 mL dose for all patients 1

Alternative Option

If racemic epinephrine is unavailable, L-epinephrine (1:1000) can be substituted at a dose of 0.5 mL/kg up to a maximum of 5 mL 1, 2. Research shows L-epinephrine is at least as effective as racemic epinephrine with no additional adverse effects 2.

Monitoring and Follow-up Protocol

Post-Administration Monitoring

  • Monitor for clinical improvement in stridor, respiratory rate, and work of breathing
  • Peak effect occurs at approximately 10-30 minutes post-administration 3, 4
  • Effect typically wanes by 2 hours post-administration 3, 4
  • Monitor vital signs including heart rate, blood pressure, respiratory rate, and oxygen saturation

Observation Period

  • Patients should be monitored for at least 2 hours after receiving racemic epinephrine 1
  • This observation period is critical to determine if symptoms recur as the medication effect wanes

Repeat Dosing Considerations

Second Dose Protocol

  • May repeat dose if symptoms recur or persist
  • According to recent guidelines, patients who receive 2 or fewer doses of racemic epinephrine may be safely discharged if symptoms resolve 1
  • Traditional practice often recommended admission after ≥2 doses, but recent evidence suggests this may not be necessary for all patients 5

Discharge Criteria After Multiple Doses

Patients can be safely discharged after multiple doses if:

  • No stridor at rest persists after treatment
  • Patient can tolerate oral fluids
  • Oxygen saturation remains ≥92% on room air 6
  • Patient appears clinically well without increased work of breathing 6

Admission Criteria

Consider hospital admission if any of the following are present:

  • Oxygen saturation <92% or cyanosis
  • Persistent significant respiratory distress after treatment
  • Stridor at rest that persists after treatment
  • Need for more than two doses of nebulized epinephrine
  • Inability to tolerate oral fluids
  • Toxic appearance 6

Important Clinical Considerations

Concurrent Medications

  • Corticosteroids: Always administer dexamethasone (0.15-0.60 mg/kg) concurrently with racemic epinephrine for optimal treatment of croup 6
  • Corticosteroids should be given even in mild cases to reduce inflammation and improve symptoms

Potential Adverse Effects

  • Tachycardia
  • Hypertension
  • Pallor
  • Tremor
  • Vomiting

Contraindications

  • Known hypersensitivity to epinephrine or any component of the formulation
  • Use with caution in patients with cardiovascular disease

By following this protocol for racemic epinephrine administration in croup, clinicians can effectively manage symptoms while minimizing unnecessary hospitalizations. The evidence supports that many patients, especially those who become asymptomatic after treatment, can be safely managed as outpatients even after receiving multiple doses of racemic epinephrine 5.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Nebulized racemic epinephrine by IPPB for the treatment of croup: a double-blind study.

American journal of diseases of children (1960), 1978

Research

Nebulized epinephrine for croup in children.

The Cochrane database of systematic reviews, 2013

Guideline

Respiratory Infections in Children

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

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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