There's nothing as scary as a severe and sudden allergic reaction (called anaphylaxis), as the body reacts to a foreign substance that produces a number of different symptoms simultaneously, and usually within mere minutes of the allergen coming into contact with the body. Anaphylactic shock will cause death if not treated.
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.
In this lesson, we'll cover what anaphylactic shock is, what it does to the body, and how we can help someone who's having a severe allergic reaction until advanced medical personnel arrive.
Anaphylaxis Effects on the Body
During a severe allergic reaction, there are two biological mechanisms working together, albeit while moving in opposite directions.
- Blood vessels relax and dilate. As this happens, blood and other fluids leak into the body's tissues, which decreases blood pressure and will eventually starve vital organs of oxygen.
- At the same time, the airway begins to tighten. The bronchioles and alveoli sacs are filling with mucus and other fluids and breathing becomes more and more difficult.
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 Provide Care
Before we get into how to use an epi-pen, let's look at some common signs and symptoms of an allergic reaction, which include:
- Hives
- Itchiness
- Swollen tongue
- Scratchy throat
- Pale
- Lightheaded
- Difficulty breathing
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. Especially if this is their first allergic reaction.
- Make sure the epi-pen isn't expired.
- 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 (or the back); you may accidentally inject yourself while treating the victim.
- Firmly push the tip of the pen into the victim'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 a minimum of three 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 (along with some epinephrine), 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 patients may experience, including:
- Rapid heartbeat
- Shakiness
- Feelings of anxiety
- Dizziness
- Headache
A Few Common Questions About Anaphylaxis
Should I administer the epinephrine, or should I let the victim do it?
Let the victim handle the epi-pen if they're able to. If dealing with a small child or someone who's unable to do it themselves, assist as needed. If you do have to assist, try and get permission to do so for reasons of liability. The American Heart Association recommends helping in the following scenarios:
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
What if there are complications while waiting for EMS to arrive?
It's always a good idea to monitor for other issues while waiting for paramedics to arrive, like loss of consciousness, an increase in breathing difficulties, respiratory arrest, and cardiac arrest.
If the person stops breathing but still has a pulse, perform rescue breathing. If the victim stops breathing and loses his or her pulse, begin full CPR.
Pro Tip #3: Remember, you can always call 911 and put the phone on speaker. Dispatch can help walk you through any first aid scenarios you may not be comfortable with. Also, it's important to understand that once a person loses consciousness and a pulse, they're technically already dead. And there's no way to make that situation any worse.
If the victim begins showing signs of shock – cool, pale, sweaty skin and a rapid pulse – cover him or her with a sheet, coat, or blanket and keep them as warm and comfortable as possible while waiting for EMS to arrive.
Are there different doses of epinephrine?
Yes. 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.