Anaphylaxis is a severe allergic reaction that can happen shortly after exposure to an allergen. It can lead to anaphylactic shock, a life-threatening condition that causes a drop in blood pressure and narrowing of your airway.

If you have severe allergies, it’s important to know how to treat anaphylaxis. For added safety, make sure those close to you also know what to do if you start showing signs of anaphylaxis.

Read on to learn how to recognize and treat anaphylaxis.

Anaphylaxis symptoms usually start within 5 to 30 minutes of contact with an allergen. But for some people, it can take up to an hour before any symptoms appear.

Signs and symptoms of anaphylaxis include:

  • red rash with hives
  • itching
  • flushed skin
  • throat swelling/tightness
  • swollen tongue
  • wheezing
  • chest tightness
  • hoarseness
  • trouble swallowing
  • nausea
  • vomiting
  • stomach cramping and pain
  • diarrhea
  • low blood pressure
  • weak or rapid heartbeat
  • feeling of impending doom

Take a look at these 11 photos of anaphylaxis symptoms to help you recognize them.

Some people have a second wave of similar symptoms after the initial onset. This is called biphasic anaphylaxis. It can happen anywhere from 1 to 72 hours after the initial attack, but usually occurs within 8 to 10 hours. This is why it’s very important to seek medical treatment if you experience anaphylaxis.

Anaphylactic shock

Anaphylaxis sometimes results in a type of shock called anaphylactic shock.

Signs of anaphylactic shock include:

  • gasping for air
  • dizziness
  • confusion
  • weakness
  • cool and clammy skin
  • paleness
  • loss of consciousness

The main anaphylaxis treatment is an epinephrine injection. If you or someone else is having a severe allergic reaction and you don’t have any epinephrine, call 911 or head to the nearest hospital.

Learn more about why anaphylaxis always requires emergency treatment.

You can administer epinephrine to yourself or others using an epinephrine auto-injector (EpiPen, Adrenalain, Adrenaclick, Auci-Q, Twinject). This is a prefilled automatic injection device that you use to inject epinephrine into the skin and muscle at the first signs of anaphylaxis.

Epinephrine injections work by relaxing the muscles in your airway and constricting your blood vessels to increase blood pressure.

There are several types of epinephrine auto-injectors, and they’re used slightly differently. Make sure to go over the instructions that come with yours.

Generally, giving an epinephrine injection involves:

  1. holding the auto-injector with the tip pointing down
  2. removing the safety cap by pulling it upward
  3. pushing the tip into the mid-outer thigh until you hear a click sound

If giving the injection to a child, make sure to hold to hold their leg study. In an emergency, you can give an injection through clothing.

Next steps

After administering the injection, call 911 or head to the emergency room, even if symptoms improve. The person having the reaction should lie down with their legs elevated while they wait.

If their tongue or throat is swollen or they’re having trouble breathing, they should stay upright and lean forward. Pregnant women should lie on their left side.

If someone is still having anaphylaxis symptoms after five minutes, you can administer a second injection. Just make sure you wait at least five minutes in between injections.

Epinephrine injections are the standard for anaphylaxis treatment. Once someone arrives at a hospital, they may be given additional treatments, including:

  • oxygen
  • antihistamines
  • beta-agonist inhaler
  • more epinephrine

More severe cases may require a breathing tube or surgery to open up the airway.

Make sure to tell hospital staff if you’ve already given yourself or someone else an epinephrine injection.

Corticosteroids were once used as a first-line treatment for severe allergic reactions and anaphylaxis, but this is no longer recommended. A 2017 review found that steroids weren’t conclusively an effective treatment option. However, the study found that they are “rational and beneficial” as an adjunct therapy alongside epinephrine. They can also produce a range of side effects, but these are seldom seen in short-term use.

If you have severe allergies or a history of anaphylaxis, make sure that those close to you are aware and know how to recognize the signs of a reaction. Quick treatment is crucial, and someone showing signs of anaphylaxis should also seek emergency treatment, even after an injection.

Keep an epinephrine auto-injector on hand and always try to have a backup one. Make sure to note the expiration date on your auto-injector so you can get a refill before it expires. For added protection, consider wearing medical alert jewelry that indicates your allergies.