Epipen®: a brand name for an epinephrine auto-injector device used to manage potentially life-threatening anaphylactic reactions to allergens. Epinephrine is the first-line treatment for life-threatening allergic reactions. Patients are recommended to have an epinephrine auto-injector immediately available if they have a history of life-threatening allergic reactions (anaphylaxis) to things like bee stings, peanuts or seafood, or are at increased risk for a severe allergic reaction. Those at high risk are recommended to have two sources of epinephrine available at all times. Epipens contain a single dose of epinephrine that is injected into the outer thigh if signs of a serious allergic reaction are present.