Epinephrine is the first line of defense when it comes to treating anaphylaxis. And the sooner it's administered, the less severe the allergic reaction.

Remember, anaphylaxis is a severe and sudden allergic reaction that affects many parts of the body at the same time within mere minutes of the allergen coming into contact with the body.

Anaphylaxis can cause the body's blood vessels to suddenly dilate, which can lead to anaphylactic shock. Anaphylactic shock can cause a sudden drop in blood pressure resulting in organs like the brain quickly becoming oxygen starved. Anaphylactic shock will cause death if not treated.

People with a history of allergic reactions should always carry an epinephrine pen. Pens are single dose, pre-filled, automatic injection devices, also known as epi pens.

The following instructions are specifically for Epi Pen brand. If you're using a different brand of epi pen, be sure to follow the manufacturer's instructions.

How to Use an Epi Pen

Pro Tip #1: Any time an epi pen is used, be sure to call 911 and activate EMS. The person, even if feeling better, must seek further medical attention after a severe allergic reaction.

  • Remove the pen's safety cap.
  • Grip the pen in your hand with the tip pointing down.

Warning: Never put your thumb, fingers, or hand over the tip of the pen; you may accidentally inject yourself while treating the patient.

  • Firmly push the tip of the pen into the patient's outer thigh at a 90-degree angle and until you hear the pen click. Needles can penetrate clothing.
  • Keep the auto injector firmly pressed against the patient's thigh; hold for 3 seconds.
  • Pull the epi pen straight out.

Warning: Make sure you don't pull the pen out at an angle. This can cause a lot of pain and bleeding. And if blood comes out of the leg, there's a good chance the effectiveness of the shot will be reduced.

  • Rub the area for 10 seconds, as this will increase absorption of the epinephrine within the leg muscle.

Pro Tip #2: A second epi pen may be used if symptoms persist or recur and if EMS has been delayed for more than 5 to 10 minutes.

Usually the patient will notice some airway relief pretty quickly, as the tightness in the throat begins to dissipate. There are, however, some unfortunate side effects that some patient's may experience, including:

  • Rapid heartbeat
  • Shakiness
  • Feelings of anxiety
  • Dizziness
  • Headache

Pro Tip #3: Once you administer an epinephrine injection, make note of the time it was delivered and tell EMS when they arrive.

A Word About Epinephrine

Epinephrine is a drug that slows or stops the effects of anaphylaxis. If a patient is known to have an allergy that could lead to anaphylaxis, they may carry an epinephrine auto-injector (an epi pen) that can deliver a single dose of the drug.

Epinephrine devices are available in different doses, as the dose of epinephrine is based on weight – 0.15 mg for children weighing between 33 and 66 pounds, and 0.3 mg for children and adults weighing more than 66 pounds. People with a known history of anaphylaxis would be wise to carry an anaphylaxis kit containing at least two doses of epinephrine with them at all times.

Why a second dose? Because more than one dose may be needed to stop a strong anaphylactic reaction. It's important to remember that a second dose is administered only if emergency medical responders are delayed and the patient is still having signs and symptoms of anaphylaxis 5 to 10 minutes after administering the first dose.

It's important to act fast when a patient is having an anaphylactic reaction, as difficulty breathing and shock are both life-threatening conditions that could suddenly erupt. If the patient is unable to self-administer the medication, you may need to help them with the epi pen.

Only assist if/when:

  • The patient has a previous diagnosis of anaphylaxis and has been prescribed an epinephrine auto-injector
  • The patient is having signs and symptoms of anaphylaxis
  • The patient requests your help using an auto-injector
  • Your state laws permit giving assistance