From the Guidelines
The prescription for an EpiPen (epinephrine auto-injector) is typically 0.3 mg of epinephrine for adults and children weighing 25 kg (55 pounds) or more, and 0.15 mg for children weighing 10-25 kg (22-55 pounds). EpiPens are prescribed as a two-pack, with instructions to inject into the outer thigh muscle at the first sign of a severe allergic reaction (anaphylaxis) 1. After administration, the patient should seek immediate emergency medical care, even if symptoms improve, as the effects of epinephrine are temporary (typically 10-20 minutes). A second dose may be needed if symptoms persist or return before emergency help arrives. The medication works by constricting blood vessels to increase blood pressure, relaxing airway muscles to improve breathing, and reducing hives and swelling.
Some key points to consider when prescribing an EpiPen include:
- The dose of epinephrine, with 0.15 mg recommended for children weighing 10-25 kg and 0.3 mg for those weighing 25 kg or more 1
- The importance of proper administration technique, with injection into the outer thigh muscle 1
- The need for immediate emergency medical care after administration, even if symptoms improve 1
- The potential need for a second dose if symptoms persist or return before emergency help arrives 1
It is essential to note that the use of epinephrine auto-injectors is not without risks, and patients should be carefully selected and educated on their use 1. However, the benefits of prompt treatment of anaphylaxis with epinephrine far outweigh the risks, and delayed use of epinephrine might be ineffective 1. Patients should carry their EpiPen at all times, check the expiration date regularly, and store it at room temperature away from light. Training on proper administration technique is essential for effective emergency use.
From the FDA Drug Label
11 DESCRIPTION Adrenalin® (epinephrine injection, USP) is a clear, colorless, sterile solution containing 1 mg/mL epinephrine, packaged as 1 mL of solution in a single-use clear glass vial or 30 mL of solution in a multiple-dose amber glass vial.
16 HOW SUPPLIED/STORAGE & HANDLING EPINEPHRINE INJECTION, USP 1mg/mL 1:1000 VIAL is supplied in the following dosage forms
The prescription for an EpiPen (epinephrine auto-injector) is:
- Epinephrine injection, USP 1mg/mL, 1mL
- Dosage form: Single-use clear glass vial or multiple-dose amber glass vial
- Storage: Store between 20° to 25°C (68° to 77°F) [See USP Controlled Room Temperature]
- Handling: Protect from light and freezing. Inspect visually for particulate matter and discoloration prior to administration. 2 2
From the Research
Prescription for an EpiPen
To prescribe an EpiPen, the following details should be considered:
- The patient's weight and age to determine the appropriate dose of epinephrine, as different auto-injectors are designed for different weight ranges 3
- The availability and affordability of epinephrine auto-injectors, as well as alternative options such as epinephrine prefilled syringes 4
- The importance of proper training and demonstration of how to use the EpiPen, as well as the need for patients to carry two auto-injectors at all times 3
Key Considerations
When prescribing an EpiPen, the following factors should be taken into account:
- The risk of subcutaneous and intraosseous/periosteal injections associated with different needle lengths, particularly in children and adults with varying body mass indexes (BMIs) 5
- The pharmacokinetics and pharmacodynamics of epinephrine after administration via different routes, including intranasal and intramuscular injection 6
- The ideal needle length for epinephrine auto-injectors, which may vary depending on the patient's weight, age, and BMI 7
Dosage and Administration
The standard approved dose of epinephrine administered intramuscularly in the lateral thigh is 0.3 mg for adults and children over 30 kg, and 0.15 mg for children between 15 kg and 30 kg 3. The EpiPen should be administered promptly once anaphylaxis is suspected, and patients should be instructed on the proper technique for using the device.