What is the proper procedure for administering an EpiPen (epinephrine) to an adult or child suspected of having an anaphylactic reaction?

EpiPen Administration for Anaphylaxis

Inject epinephrine immediately into the anterolateral thigh (vastus lateralis) at the first sign of anaphylaxis—0.3 mg for adults and children ≥30 kg, or 0.15 mg for children 15-30 kg—and repeat every 5 minutes if symptoms persist or worsen. 1, 2

Immediate Recognition and Action

When you suspect anaphylaxis, do not hesitate. Delaying epinephrine administration is associated with increased mortality and morbidity. 1 Fatal anaphylaxis cases are consistently linked to delayed epinephrine, not to giving multiple doses. 3

Administer epinephrine as the absolute first-line treatment without waiting for symptom progression. 1 For patients with known severe food allergies who have definitely eaten their allergen, some protocols recommend giving epinephrine immediately even before symptoms appear. 4

Exact Administration Technique

Site and Method

• Inject into the anterolateral aspect of the mid-thigh (vastus lateralis muscle)—this is the only recommended site. 1, 2
• You can inject directly through clothing if necessary. 1, 2
• This intramuscular route achieves peak plasma concentrations in 8±2 minutes, compared to 34±14 minutes with subcutaneous deltoid injection. 5, 3
• Use a needle at least 1/2 to 5/8 inch long to ensure intramuscular delivery. 2

Step-by-Step for EpiPen

1. Remove the EpiPen from its plastic carrying case 4
2. Pull off the blue safety release cap 4
3. Hold the orange tip near the outer thigh 4
4. Swing and firmly push the orange tip against the outer thigh 4
5. Hold on the thigh for approximately 10 seconds 4
6. Remove the EpiPen and massage the area for 10 more seconds 4

For Children

When administering to a child, hold the leg firmly in place and limit movement before and during injection to minimize injection-related injury. 2

Precise Dosing

Weight-Based Dosing

• Adults and children ≥30 kg: 0.3 mg (standard EpiPen) 1, 5, 2
• Children 15-30 kg: 0.15 mg (EpiPen Jr) 1, 5
• Children <30 kg: 0.01 mg/kg up to maximum 0.3 mg 5, 2

The FDA-approved dosing is 0.3 to 0.5 mg for adults and children ≥30 kg, with a maximum single dose of 0.5 mg per injection. 2

Repeat Dosing Protocol

Repeat the injection every 5 minutes if symptoms persist, worsen, or recur. 1, 2 There is no maximum number of doses—continue dosing every 5 minutes as needed until symptoms resolve. 3 Approximately 10-20% of patients require more than one dose, and some patients need multiple doses. 5, 3

Critical Points on Repeat Dosing

• Do not stop at one dose if symptoms persist or progress. 3
• Do not administer repeated injections at the same site, as vasoconstriction may cause tissue necrosis. 2
• The number of doses should be determined by clinical response, not an arbitrary maximum. 3

Concurrent Emergency Management

Immediate Actions After Injection

1. Call 911 immediately or activate emergency medical services 1, 3
2. Position the patient supine with legs elevated (unless respiratory distress prevents this) 1, 3
3. Never allow the patient to stand or walk—this increases mortality risk 3
4. Begin monitoring vital signs and watch for symptom progression 4

Additional Medications (Secondary to Epinephrine)

After giving epinephrine, consider:

• H1 antihistamine (diphenhydramine 25-50 mg parenterally) 3
• H2 antihistamine (ranitidine 50 mg IV over 5 minutes) 3
• Bronchodilator inhaler if the patient has asthma 4

However, antihistamines and bronchodilators cannot be depended upon to treat severe reactions—only epinephrine is effective. 4

Post-Administration Requirements

All patients must be transported to the emergency department via EMS for observation, even if symptoms completely resolve. 1, 3 Anaphylaxis can have biphasic reactions, and continued monitoring is essential.

At discharge, prescribe two epinephrine autoinjectors of the appropriate dose for home use. 1, 5, 3 Approximately 10-20% of patients require a second dose, making dual prescriptions necessary. 5

Special Populations and Safety

Patients with Cardiovascular Disease

There is no absolute contraindication to epinephrine in anaphylaxis, even in elderly patients or those with cardiac disease. 3 The risk of death from untreated anaphylaxis far exceeds the risk of epinephrine-related cardiac effects. 1, 3

Patients with Asthma

Patients with asthma are at higher risk of fatal anaphylaxis and require particularly prompt epinephrine administration. 1

Critical Pitfalls to Avoid

1. Delaying administration while waiting for "more severe" symptoms—this can be fatal 1, 6, 7
2. Using the wrong site (deltoid or subcutaneous)—this delays peak effect from 8 minutes to 34 minutes 5, 3
3. Stopping at one dose prematurely when symptoms persist or recur 3
4. Confusing concentrations—always use 1:1000 (1 mg/mL) for intramuscular injection; 1:10,000 is reserved for IV use only 3
5. Relying on antihistamines or bronchodilators as primary treatment—these do not treat anaphylaxis 4

When to Escalate Beyond Intramuscular Epinephrine

If the patient fails to respond to multiple intramuscular doses (typically after 2-3 doses), consider transitioning to IV epinephrine infusion. 3 This requires continuous hemodynamic monitoring, starting at 1-4 mcg/min and titrating up to a maximum of 10 mcg/min. 3 IV epinephrine should only be used in specific situations including cardiac arrest or refractory shock, as it carries significant risk of dilution/dosing errors and serious adverse effects. 3

For severe cases, also administer normal saline bolus of 1000-2000 mL for adults, and consider hydrocortisone and famotidine. 3