What is the proper procedure for administering an EpiPen (epinephrine) in a clinic?

How to Use an EpiPen in the Clinic

Inject epinephrine 0.3-0.5 mg intramuscularly into the anterolateral mid-thigh immediately upon recognizing anaphylaxis, and be prepared to repeat the dose every 5-10 minutes if symptoms persist or worsen. 1

Recognition of Anaphylaxis

Before administering epinephrine, confirm anaphylaxis by identifying:

• Acute onset (minutes to hours) with skin/mucosal involvement (hives, flushing, swollen lips/tongue) PLUS respiratory compromise (wheeze, stridor, dyspnea) OR hypotension/syncope 2
• Two or more organ systems involved after allergen exposure: skin, respiratory, cardiovascular, or gastrointestinal symptoms 2
• Isolated hypotension after known allergen exposure 2

Critical caveat: Skin signs may be absent in 10% of anaphylaxis cases, so do not wait for hives to appear before treating 2

Immediate Administration Steps

Dosing

• Adults and children ≥30 kg: 0.3-0.5 mg (maximum 0.5 mg per injection) 1
• Children <30 kg: 0.01 mg/kg (maximum 0.3 mg per injection) 1
• Autoinjector options: 0.15 mg (EpiPen Jr) or 0.3 mg (EpiPen) 2

Injection Technique

• Inject into the anterolateral mid-thigh (vastus lateralis muscle) through clothing if necessary 1, 2
• Use a needle at least 1/2 to 5/8 inch long to ensure intramuscular delivery 1
• Hold the child's leg firmly to minimize movement and injection-related injury 1
• Do not inject the same site repeatedly as vasoconstriction causes tissue necrosis 1

Why the thigh matters: Intramuscular injection in the vastus lateralis achieves peak plasma concentrations in 8±2 minutes, compared to 34±14 minutes with subcutaneous deltoid injection 2

Repeat Dosing Protocol

• Repeat injection every 5-10 minutes if symptoms fail to resolve or worsen 1, 2
• 6-28% of patients require a second dose, and rarely a third 2, 3
• Monitor continuously for response: airway patency, breathing adequacy, blood pressure, and skin perfusion 1

Concurrent Management

While administering epinephrine:

• Call 911 or activate resuscitation team immediately 2
• Position patient supine with legs elevated, or in position of comfort if respiratory distress/vomiting present 2
• Never allow standing or walking as this increases mortality risk 2
• Prepare for additional interventions: oxygen, IV fluids, antihistamines, corticosteroids 2

Severe/Refractory Cases

If hypotension persists despite 2-3 doses of intramuscular epinephrine:

• Administer normal saline bolus 1000-2000 mL for adults 2
• Consider IV epinephrine infusion (requires dilution to avoid overdose—reserve for hospital settings with continuous monitoring) 2
• Administer hydrocortisone 100-500 mg IV and famotidine 20 mg IV 2
• Consider albuterol nebulizer for bronchospasm 2

Critical safety point: IV epinephrine carries significant risk of dilution/dosing errors and serious adverse effects; the intramuscular route is safer and preferred for first-line treatment 2

Common Pitfalls to Avoid

• Delaying injection while waiting for "more symptoms" to develop—fatal anaphylaxis is associated with delayed epinephrine administration 2, 4
• Using subcutaneous route instead of intramuscular (slower absorption, less effective) 2
• Injecting into the arm/deltoid instead of thigh (significantly delayed peak concentrations) 2
• Underdosing due to fixed autoinjector limitations—use clinical judgment to repeat doses 2
• Using expired epinephrine which may deliver inadequate doses 5

Post-Administration

• Transport to emergency department via EMS for observation (minimum 4-6 hours) even if symptoms resolve 2
• Biphasic reactions can occur hours later, requiring continued monitoring 2
• Prescribe two autoinjectors for home use and provide training on self-administration 6