Updated 16 May 2017

Epinephrine auto-injector

Epinephrine is a medication used in emergencies to treat or prevent severe allergic reactions that can result in anaphylaxis.



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Epinephrine is in a class of medications called sympathomimetic agents because the medication mimics the properties of the sympathetic nervous system. Epinephrine is a medication used in emergencies to treat or prevent severe allergic reactions that can result in anaphylaxis.

Anaphylaxis is a rapid, immune-mediated (allergic), systemic reaction to allergens (like food, medication or insect stings or bites) that the individual has previously been exposed to. Anaphylaxis can be potentially life threatening. The most dangerous symptoms are low blood pressure, breathing difficulties, shock and loss of consciousness, all of which can be fatal. The most severe type of anaphylaxis, known as anaphylactic shock, usually results in death within minutes, if untreated. Anaphylactic shock is characterized by inflammation of the throat and a sudden drop in blood pressure.

Epinephrine is administered to improve breathing, stimulate the heart and reduce facial swelling during a severe allergic reaction. Epinephrine relaxes the muscles in the airways and tightens the blood vessels.

Individuals who are at risk for anaphylaxis, such as individuals allergic to bee stings, carry a prescription epinephrine auto-injector. If symptoms of anaphylaxis appear after exposure to an allergen, the patient uses the device to inject the epinephrine into his/her thigh. A trained family member of friend may help the patient administer the epinephrine, if necessary.


Epinephrine auto-injectors are disposable, one-time-use devices, which contain a single dose of epinephrine. Use epinephrine injection exactly as directed.

An epinephrine auto-injector is self-administered by way of injection. Some individuals, especially children, may need assistance administering the medication. It is recommended that friends and family members of the patient learn how to properly administer the medication, in case of an emergency.

To use, remove the safety cap, and remove the auto-injector from its storage tube.

Hold the device with the black tip facing downward.

Release the safety cap with the other hand.

Swing and jab the auto-injector into the outer thigh until the device clicks. The auto-injector should be at a 90-degree angle to the thigh. The needle may be injected through clothing that is covering the thigh.

Hold the device firmly against the thigh for about 10 seconds. The injection is now complete.

Remove the device from the thigh and rub the area with the hand.

Carefully place the auto-injector, needle-end first, into the storage tube. Screw the cap. Go the nearest hospital emergency room immediately. Bring the auto-injector, and tell the physician that the device was used. The physician will dispose of the device.

If the epinephrine is accidentally injected into any part of the body other than the thigh, go to the nearest hospital emergency room immediately.


Individuals who have experienced severe allergic reactions in the past or have known allergies that may cause anaphylaxis should consult their healthcare providers to determine whether an epinephrine auto-injector should be prescribed. Severe allergic reactions are most commonly triggered by food (especially peanuts, shellfish, fish, milk and eggs), insect stings/bites, latex and medications (especially antibiotics and anti-seizure medicines).


Side effects may include upset stomach, vomiting, sweating, dizziness, nervousness, weakness, pale skin, increased blood pressure, headache and shaking. The effects of the injection begin to wear off after 10 to 20 minutes.

Serious side effects may include difficulty breathing or irregular heartbeat. These symptoms are rare, and patients should call their healthcare provider immediately if they experience them.


Patients should tell their qualified healthcare providers if they have heart conditions, high blood pressure, thyroid disease or allergies (especially drug allergies) because epinephrine can potentially worsen their conditions. Patients should also tell their doctor if they have diabetes because epinephrine can potentially increase or decrease the blood-glucose-lowering effect of insulin.

Patients should inform their healthcare providers if they are taking any prescription or over-the-counter medication, vitamins, nutritional supplements or herbal supplements.

Pregnancy: Patients who are pregnant or thinking about becoming pregnant should consult their healthcare providers. It is unknown whether epinephrine is excreted in breast milk. Patients are advised to consult a qualified healthcare provider to discuss the risks and benefits of using epinephrine during pregnancy or breastfeeding.


Patients should consult a qualified healthcare provider to determine whether an epinephrine auto-injector may interact with other medicines they are taking. A healthcare provider should be consulted before starting, stopping or changing the dose of any medication.

Antidepressants: Antidepressants like amitriptyline (Limbitrol©), desipramine (Norpramin© or Pertofrane©) or nortriptyline (Aventyl© or Pamelor©) may cause side effects such as headache and high blood pressure. Therefore, antidepressants may increase the risk of side effects, such as headache and high blood pressure, which are associated with epinephrine use.

Catechol-O-methyltransferase (COMT) inhibitors: Catechol-O-methyltransferase (COMT) inhibitors like entacapone may increase the risk of irregular heartbeat after epinephrine administration. Other drugs used to treat irregular heartbeat, such as digoxin or quinidine may also increase the risk of adverse effects.

Agents that increase blood pressure: Fludrocortisone (Florinef©) and midodrine (ProAmatine©) may increase the risk of cardiovascular side effects of epinephrine, such as increased blood pressure and heartbeat.


Anaphylaxis is considered a medical emergency that requires immediate medical care. Therefore, integrative therapies should not be used in place of conventional medicine when an individual has an anaphylactic reaction.


The epinephrine auto-injector should be kept inside the plastic carrying tube and out of reach of children.

Store the medication in a dark place at room temperature. Avoid exposure to heat and moisture.

Dispose of the device once the expiration date has passed or if the liquid has changed color, is cloudy or contains solid particles.


This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (

  • American Academy of Allergy Asthma & Immunology. Anaphylaxis. Accessed March 16, 2007.
  • Natural Standard: The Authority on Integrative Medicine. Copyright © 2008. Accessed March 16, 2007.
  • Neugut AL, Ghatak AT, Miller RL. Anaphylaxis in the United States: An investigation into its epidemiology. Archives of Internal Medicine 61 (1): 15-21. 2001.
  • Portnoy JM, Moffitt JE, Golden DB, et al. Stinging Insect Hypersensitivity: A Practice Parameter. J Allergy Clin Immunol. 1999 May;103(5 Pt 1):963-80. View abstract
  • Sussman GL and Beezhold DH. Allergy to latex rubber. Annals of Internal Medicine 122 (1): 43-6. 1995. View abstract
  • The Food Allergy & Anaphylaxis Network. Accessed March 16, 2007.
  • Valentine M.D, Lichtenstein, LM. Anaphylaxis and Stinging Insect Hypersensitivity. Journal of the American Medical Association. (1992) 268:2830-2833. View abstract

Copyright © 2011 Natural Standard (


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Dr Morris is the Principal Allergist at the Cape Town and Johannesburg Allergy Clinics with postgraduate diplomas in Allergology, Dermatology, Paediatrics and Family Medicine dealing with both adult and childhood allergies. obesity and diabetes societies and runs a trial centre for new drugs.

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