From the Guidelines
The recommended dose of epinephrine for anaphylaxis is 0.01 mg/kg of 1 mg/mL (1:1000), up to 0.5 mg in adults and 0.3 mg in children, administered intramuscularly into the anterolateral thigh. This dose should be given immediately upon recognition of anaphylaxis symptoms, and can be repeated every 5 to 15 minutes if symptoms persist or worsen 1. Key points to consider in the administration of epinephrine for anaphylaxis include:
- The dose should be administered intramuscularly, as this provides faster absorption and higher plasma concentrations compared to subcutaneous administration 1.
- Auto-injectors, such as EpiPen, are available in 0.3 mg for adults and 0.15 mg for children, making administration simpler in emergency situations 1.
- There are no absolute contraindications to the use of epinephrine in anaphylaxis, and it should be administered promptly in all cases of suspected anaphylaxis 1.
- After administering epinephrine, the patient should be placed in a supine position with legs elevated (unless respiratory distress is present), and emergency medical services should be called immediately 1. Epinephrine works by constricting blood vessels to increase blood pressure, relaxing airway muscles to improve breathing, and reducing hives and swelling, making it the first-line treatment for anaphylaxis due to its ability to address multiple physiological aspects of the allergic reaction simultaneously 1.
From the FDA Drug Label
DOSAGE AND ADMINISTRATION Anaphylaxis: Adults and Children 30 kg (66 lbs) or more: 0.3 to 0.5 mg (0.3 to 0.5 mL) intramuscularly or subcutaneously into anterolateral aspect of the thigh every 5 to 10 minutes as necessary Children 30 kg (66 lbs) or less: 0.01 mg/kg (0.01 mL/kg), up to 0.3 mg (0.3 mL), intramuscularly or subcutaneously into anterolateral aspect of the thigh every 5 to 10 minutes as necessary
The recommended dose of epinephrine (Epi) for anaphylaxis is:
- 0.3 to 0.5 mg (0.3 to 0.5 mL) for adults and children 30 kg (66 lbs) or more, administered intramuscularly or subcutaneously into the anterolateral aspect of the thigh.
- 0.01 mg/kg (0.01 mL/kg), up to 0.3 mg (0.3 mL), for children 30 kg (66 lbs) or less, administered intramuscularly or subcutaneously into the anterolateral aspect of the thigh. Administration may be repeated every 5 to 10 minutes as necessary 2.
From the Research
Push Dose Epi Administration
- The recommended dose of epinephrine (Epi) for anaphylaxis in adults is 0.3-0.5 mg, injected intramuscularly in the anterolateral aspect of the mid-thigh 3, 4.
- For children, the recommended dose is 0.01 mg/kg, given in the lateral thigh 4.
- Epinephrine should be administered as soon as the diagnosis of anaphylaxis is suspected, and any delays in recognition or initiation of therapy can result in unnecessary increases in patient morbidity and mortality 5.
Route of Administration
- The most effective route of administration for epinephrine in anaphylaxis is intramuscularly, as it has a faster onset of action compared to subcutaneous injection 3.
- Intravenous administration of epinephrine is not recommended due to the increased risk of adverse effects 3.
Multiple Doses
- While multiple epinephrine doses may be required to treat severe anaphylaxis, 90% of anaphylaxis cases do not require more than 1 epinephrine dose 6.
- A "1-2-3" approach to anaphylaxis treatment is recommended, where a second dose of intramuscular epinephrine is considered if the initial response is not adequate, and a third dose is considered if the response is still not adequate 6.
Education and Access
- Education on the proper use of epinephrine auto-injectors is paramount for patients with known anaphylactic reactivity 4.
- Strategies to improve education and access to appropriate drugs, such as labelled "anaphylaxis boxes" on resuscitation trolleys, may be necessary to ensure junior doctors are equipped to make immediate management decisions in patients with anaphylaxis 7.