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What is anaphylactic shock?

Anaphylactic shock (or anaphylaxis) is a dramatic, life-threatening allergic reaction that can involve the skin, lungs, digestive tract and heart.

Common triggers include food, medication, insect bites or stings, and latex.

Symptoms of anaphylaxis most often start within minutes to an hour after exposure to the trigger. In rare cases, the reaction can start hours after contact with the trigger.

The reaction may start with tingling, itching or a metallic taste in the mouth, and then cause hives, warm skin, difficulty breathing, swelling of the mouth and throat, vomiting, diarrhea, cramping, a drop in blood pressure, dizziness or passing out.

Treatment for anaphylaxis should start right away, according to the American College of Allergy, Asthma & Immunology. A drug called epinephrine (adrenaline) is the primary treatment for anaphylaxis. It should be injected into your thigh as soon as symptoms start, and then someone should call 911. If epinephrine is not available, call 911 immediately.

The symptoms of anaphylaxis can stop and then start again after a few hours. You should stay in the hospital for monitoring to ensure that the reaction has passed. If the symptoms recur after you leave, you may not get back in time.

Prevention for anaphylaxis includes carefully avoiding anything you have severe reactions to. If you have a severe food allergy, check food labels and ask questions about ingredients and cooking methods every time you grocery shop or go out to eat. Even a trace of the trigger can cause severe reactions in some people.

If you're allergic to insect stings, reduce your risk by not wearing brightly colored clothing, not using scented skin or hair products, always wearing shoes and keeping insect spray at hand when you're outside.

Preparation for anaphylaxis includes talking to your doctor if you've ever had a strong reaction to latex, a medicine, food or an insect sting, or if you have food allergies and asthma. Your doctor may prescribe epinephrine for you to carry at all times in case of a dangerous reaction.

If you know you're severely allergic to anything, wear a medical alert bracelet, and tell your family and friends how to help you if you start having anaphylaxis symptoms.

Reviewed 9/15/2022

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