Two Concentrations, Two Purposes
Epinephrine 1 mg/mL (1:1,000) is used intramuscularly for anaphylaxis and severe asthma. Epinephrine 0.1 mg/mL (1:10,000) is used intravenously or intraosseously in cardiac arrest. Mixing these up can cause serious harm, so memorize which concentration goes with which route.
Anaphylaxis Dosing
The adult dose for anaphylaxis is typically 0.3 to 0.5 mg IM in the lateral thigh. Pediatric patients receive 0.01 mg/kg, up to 0.3 mg, and auto-injectors come in adult and pediatric strengths. The vastus lateralis is preferred because absorption is faster than from the deltoid.
Effects and Cautions
Epinephrine is an alpha and beta agonist that causes bronchodilation, vasoconstriction, and increased heart rate and contractility. Expect tachycardia, anxiety, tremors, and hypertension. Use caution in patients with cardiac history, but remember that in true anaphylaxis there is no absolute contraindication.