Epinephrine
Hormone and neurotransmitter for anaphylaxis, cardiac arrest, and shock
Indications
- Anaphylaxis via autoinjector
Contraindications
No absolute contraindications to epinephrine use in life-threatening situations such as anaphylaxis.
Cautions
- Cardiovascular disease
- Hypertension
- Diabetes
- Hyperthyroid
- Cerebrovascular disease
Adult Dosages
Anaphylaxis
- 1 dose via autoinjector to lateral thigh as directed by device instructions
- If no response after 5 minutes, may be repeated once via new autoinjector.
Pediatric Considerations
Anaphylaxis
- 1 dose via autoinjector to lateral thigh as directed by device instructions
- If no response after 5 minutes, may be repeated once via new autoinjector.
Preparation and Administration
Infusion
Adult
Standard solution concentrations:
- 4 mcg/mL: dilute 1mg in 250 mL NS
- 12 mcg/mL: dilute 3 mg in 250 mL NS
Pediatric
Standard solution concentrations:
- 4mcg/mL: dilute 1mg in 250mL NS
- 25 mcg/mL: dilute 1.25mg in 50mL NS
Direct
Standard concentration adult and pediatric:
- 10mcg/mL: dilute 0.1mg in 9mL of NS
- Withdraw 0.1mg (1mL) of 1mg/10mL prefilled syringe in 20mL syringe
- Dilute with 9mL of NS
Adverse Effects
- Common reactions to systemically administered epinephrine include anxiety, tremor, dizziness, sweating, palpitations, headache, and nausea
- Increase heart rate and blood pressure and risk of arrhythmias
- Accidental injection of epinephrine into a digit, hands, or feet may result in a loss of blood flow to the area
- Extravasation may cause ischemia or tissue necrosis
Additional Information
Mechanism of Action
Epinephrine acts on alpha and beta-adrenergic receptors. Alpha-adrenergic activity produces vasoconstriction and reduces vascular permeability; beta-adrenergic activity results in bronchial smooth muscle relaxation, increased heart rate, and increased force of cardiac contractility. Epinephrine also inhibits histamine release.
Pharmacokinetics
| Route | Onset | Peak | Duration |
|---|---|---|---|
| IV | 30 seconds | 3-5 minutes | 5-10 minutes |
| IM | 30-90 seconds | 4-10 minutes | 5-10 minutes |
Overdose
Epinephrine overdose may produce significantly elevated blood pressures and heart rate, which may in turn cause cerebral hemorrhage.
Warnings and Precautions
EPINEPHrine vials must be stored in specially marked containers and never co-mingled with other medications in kits or bins. Inadvertent administration of EPINEPHrine to patients has the potential to cause serious harm or death.
Patients with underlying coronary artery disease may develop signs and symptoms of angina or myocardial ischemia. Caution should be exercised in these cases.
Caution should be used in patients with significant tachydysrhythmias or in the context of hypothermia.
Drug Interactions
Arrhythmias can develop in patients taking antiarrhythmic medications. Beta-adrenergic blocking drugs can limit the effectiveness of EPINEPHrine's bronchodilating and inotropic effects.