How should I write a prescription for an epinephrine auto‑injector (EpiPen)?

How to Write a Prescription for an Epinephrine Auto-Injector

Prescribe TWO epinephrine auto-injectors with weight-based dosing: 0.15 mg for patients 10-25 kg and 0.3 mg for patients ≥25 kg, with clear instructions for intramuscular injection into the mid-outer thigh and a written anaphylaxis emergency action plan. 1, 2

Prescription Components

Dose Selection Based on Weight

• Patients weighing 10-25 kg (22-55 lbs): Prescribe 0.15 mg auto-injector 1, 3
• Patients weighing ≥25 kg (≥55 lbs): Prescribe 0.3 mg auto-injector 1, 3
• Infants <10 kg: Prescribe 0.15 mg auto-injector despite 1.5-fold overdosing, as this is safer than the ampule/syringe method which is error-prone and causes dangerous delays 3, 4

Quantity to Prescribe

Always prescribe TWO auto-injectors 1, 5. This is critical because:

• 7-18% of patients require a second dose during anaphylaxis 2, 5
• The first device may be accidentally activated before use 6
• One should be available at home and one at school/work 1

Prescription Format

Write the prescription as:

• Drug name: EpiPen® 0.3 mg (or 0.15 mg) auto-injector OR generic equivalent (epinephrine injection, USP)
• Quantity: Dispense 2 auto-injectors
• Directions: "Inject intramuscularly into mid-outer thigh at first sign of anaphylaxis. May repeat dose after 5-15 minutes if symptoms persist or recur. Call 911 immediately after first dose." 1, 6
• Refills: Provide adequate refills to replace before expiration dates 1

Critical Instructions to Provide

Administration Technique (from FDA label) 6

1. Remove auto-injector from protective case
2. Remove blue safety cap (do NOT flip off with thumb)
3. Hold orange tip against mid-outer thigh at 90° angle
4. Push firmly until device clicks and hold for 3 full seconds (critical step—inadequate hold time results in incomplete dosing)
5. Orange needle end will extend after activation
6. Can inject through clothing if needed

When to Use 1, 7

Inject immediately if ANY of these symptoms occur after allergen exposure:

• Respiratory: Difficulty breathing, wheezing, throat tightness, hoarseness
• Cardiovascular: Dizziness, weak pulse, hypotension, loss of consciousness
• Skin: Widespread hives, facial/lip swelling
• Gastrointestinal: Persistent vomiting, severe cramping

After Injection 1, 5

• Call 911 immediately even if symptoms improve
• Transport to emergency department for 4-6 hours observation minimum
• Second dose may be given 5-15 minutes after first if symptoms persist or recur 1, 2
• Position patient lying down with legs elevated (unless respiratory distress requires upright position) 2

Required Accompanying Documentation

Written Emergency Action Plan 1

Must include:

1. Patient's specific allergen triggers
2. Step-by-step instructions for recognizing anaphylaxis
3. When and how to administer epinephrine
4. Emergency contact numbers
5. Plan for monitoring expiration dates

Additional Prescriptions to Consider 1

• H1 antihistamine (diphenhydramine 1-2 mg/kg, max 50 mg)
• Albuterol inhaler if patient has asthma
• Note: These are adjunctive only—epinephrine is first-line and cannot be replaced by antihistamines or bronchodilators

Common Pitfalls to Avoid

Underprescribing quantity: The most critical error is prescribing only one auto-injector. Multiple studies confirm 7-18% need a second dose, and accidental activation of the first device is common 2, 5, 6.

Wrong injection site: Emphasize the mid-outer thigh (vastus lateralis) is the only appropriate site. Subcutaneous deltoid injection results in delayed absorption (peak at 34 minutes vs. 8 minutes for IM thigh) 3.

Inadequate patient education: Studies show nearly 50% of patients cannot use the device correctly after receiving a prescription 8. Demonstrate with a trainer device and have the patient practice before leaving your office 3, 6.

Failing to address cost barriers: With increasing high-deductible plans, cost is a major reason patients don't carry two devices 9. Discuss generic alternatives and patient assistance programs.

Not providing refills: Auto-injectors expire approximately every 12-18 months. Build in a system for expiration date monitoring and timely refills 1.

Special Populations

Obese patients: Consider using ideal body weight for dose selection, though practices vary 10. The 0.3 mg dose is appropriate for most patients ≥25 kg regardless of obesity.

Patients on beta-blockers: No absolute contraindication to epinephrine exists 11. These patients may require glucagon for refractory hypotension, but still prescribe epinephrine as first-line.

Rural settings: These patients may have longer EMS response times, making the two-dose prescription even more critical 12.