What is the intravenous (IV) dose of epinephrine for anaphylaxis?

Intravenous Epinephrine Dosing for Anaphylaxis

Intravenous epinephrine for anaphylaxis should be reserved for severe cases unresponsive to intramuscular epinephrine or for hospital settings, with a recommended dose of 0.1 mg (100 mcg) given slowly over 5 minutes. 1

Preferred Route of Administration

Intramuscular (IM) injection is strongly preferred over intravenous (IV) administration for anaphylaxis due to:

• Faster absorption compared to subcutaneous (SC) injection (8±2 minutes for IM vs. 34±14 minutes for SC) 1
• Significantly lower risk of cardiovascular complications and overdose 2
• Safer profile with fewer adverse effects 1

Intravenous Epinephrine Use

IV epinephrine should only be considered when:

• Patient is unresponsive to repeated IM epinephrine injections
• Patient is in a monitored hospital setting with appropriate expertise
• Patient has severe, life-threatening anaphylaxis with cardiovascular collapse 1, 3

Risks of IV Epinephrine

The risk profile of IV epinephrine is concerning:

• 10% risk of adverse cardiovascular events with IV bolus compared to 1.3% with IM administration (odds ratio 8.7) 2
• 13.3% risk of overdose with IV bolus compared to 0% with IM administration 2
• Potential for serious complications including cardiac arrhythmias, myocardial ischemia, and stroke 1, 4

Standard Dosing Protocol for Anaphylaxis

1. First-line treatment: IM epinephrine

   • Adults and children ≥30 kg: 0.3-0.5 mg (0.3-0.5 mL of 1:1000 solution)
   • Children <30 kg: 0.01 mg/kg (0.01 mL/kg of 1:1000 solution), maximum 0.3 mg 1

2. For IV administration (only if IM route fails or in critical situations):

   • Use a more dilute 1:10,000 solution (0.1 mg/mL)
   • Administer 0.1 mg (1 mL of 1:10,000 solution) slowly over 5 minutes
   • For continuous infusion: 1-4 μg/minute, titrated to response 1

Critical Safety Considerations

• IV epinephrine administration has been associated with iatrogenic overdose and potentially lethal cardiac complications 4
• Confusion about proper dosing between cardiac arrest (higher IV dose) and anaphylaxis (lower dose) has led to serious medical errors 4
• Always ensure proper labeling and differentiation between IM and IV epinephrine preparations 4
• Continuous cardiac monitoring, frequent blood pressure measurements, and pulse oximetry are mandatory when administering IV epinephrine 1

Additional Management

While administering epinephrine:

• Provide supplemental oxygen
• Initiate aggressive fluid resuscitation for intravascular volume depletion
• Consider second-line medications (antihistamines, corticosteroids) but never delay epinephrine administration 1, 3

Common Pitfalls to Avoid

1. Delaying epinephrine administration while giving antihistamines or corticosteroids first
2. Confusing cardiac arrest dosing with anaphylaxis dosing
3. Using IV route when IM would be safer and equally effective
4. Inadequate monitoring after IV epinephrine administration
5. Failure to repeat epinephrine doses every 5-10 minutes if symptoms persist 1