EpiPen (epinephrine auto-injector, EpiPen Jr)

  • Pharmacy Author:
    Omudhome Ogbru, PharmD

    Dr. Ogbru received his Doctorate in Pharmacy from the University of the Pacific School of Pharmacy in 1995. He completed a Pharmacy Practice Residency at the University of Arizona/University Medical Center in 1996. He was a Professor of Pharmacy Practice and a Regional Clerkship Coordinator for the University of the Pacific School of Pharmacy from 1996-99.

  • Medical and Pharmacy Editor: John P. Cunha, DO, FACOEP
    John P. Cunha, DO, FACOEP

    John P. Cunha, DO, FACOEP

    John P. Cunha, DO, is a U.S. board-certified Emergency Medicine Physician. Dr. Cunha's educational background includes a BS in Biology from Rutgers, the State University of New Jersey, and a DO from the Kansas City University of Medicine and Biosciences in Kansas City, MO. He completed residency training in Emergency Medicine at Newark Beth Israel Medical Center in Newark, New Jersey.

What is epinephrine auto-injector, and how does it work (mechanism of action)?


  • EpiPen is an auto-injectable epinephrine-containing device used for self-administration during life-threatening allergic reactions, including anaphylaxis. Epinephrine, the medicine contained in EpiPen, is an excitatory chemical naturally made by our bodies. Epinephrine stimulates alpha and beta-adrenergic receptors found throughout the body. When injected during an allergic reaction, epinephrine works in multiple ways to treat the many signs of anaphylaxis. It causes blood vessels to constrict or tighten which helps to increase blood pressure and decrease swelling. Epinephrine also stimulates the heart muscle, causing the heart to beat faster and pump more blood to the vital organs. Epinephrine helps patients breathe better by relaxing the muscles in the lungs and allowing the airways to open up. Additionally, it also helps to prevent further release of inflammatory chemicals that were triggered by the initial allergic reaction.
  • The FDA approved EpiPen in December 1987.

What brand names are available for epinephrine auto-injector?

EpiPen, EpiPen Jr

Is epinephrine auto-injector available as a generic drug?


Do I need a prescription for epinephrine auto-injector?


What are the uses for epinephrine auto-injector?

Epinephrine autoinjectors are used for emergency treatment of allergic reactions, including

  • anaphylactic reactions caused by inset stings or bites,
  • allergen immunotherapy,
  • foods,
  • drugs,
  • chemicals used for diagnostic testing substances such as radiocontrast media, and
  • other allergens.

EpiPen also is used for treating anaphylaxis due to exercise or unknown causes.

EpiPen is used for emergency use only and are should not replace proper medical care.

What are the side effects of epinephrine auto-injector?

Common side effects of EpiPen include:

Possible serious side effects of EpiPen include:

Medically Reviewed by a Doctor on 8/26/2016

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