Anaphylaxis is a severe allergic reaction that can be life threatening. This reaction can happen in a few minutes, or a few hours after exposure to what you are allergic to. Some people are more prone to this than others.

The symptoms of an anaphylactic reaction may at first seem similar to other allergic reactions. If this has happened to you in the past, do not let the initial mild symptoms, such as a rash, hives and itching, mislead you. Your reaction can worsen very quickly and become much more severe and life threatening within minutes.

More severe symptoms include:

  • Trouble swallowing, feeling like your throat is closing

  • Trouble breathing, wheezing

  • Hoarse voice or trouble speaking

  • Nausea, vomiting, diarrhea, stomach cramps

  • Feeling faint or lightheaded, rapid heart rate, low blood pressure

  • Becoming very drowsy, poorly responsive or trouble awakening

Sometimes the cause may be obvious, like knowing you are allergic to peanuts. To help identify your allergen, remember:

  • When it started

  • What you were doing at the time or just before that

  • Any activities you were involved in

  • Any new products or contacts

 Here are some common causes, but remember almost anything can cause a reaction, and you may not even be aware that you came into contact with one of these things.

  • Dust, mold, pollen

  • Plants, such as poison ivy and poison oak

  • Animals

  • Foods such as shrimp, shellfish, peanuts, milk products, gluten, eggs; also colorings, flavorings, additives

  • Insect bites or stings such as bees, mosquitos, flees, ticks

  • Medicines such as penicillin, sulfa drugs, amoxicillin, aspirin, ibuprofen; any medicine can cause a reaction

  • Jewelry such as nickel, or gold (new, or something you’ve worn for a while including zippers, and buttons)

  • Latex such as in gloves, clothes, toys, balloons, or some tapes (some people allergic to latex may also  have problems with foods like bananas, avocados, kiwi, papaya, or chestnuts)

  • Lotions, perfumes, cosmetics, soaps, shampoos, skincare products, nail products

  • Chemicals or dyes in clothing, linen, cleaners, hair dyes, soaps, iodine

If you are exposed to the same substance again, you may have the same or more severe reaction. Treatment for anaphylaxis is epinephrine (adrenalin). This is available by prescription as a self-injectable pen. If the cause of your reaction is known, you should avoid exposure in the future. If the cause is not known, follow up with your doctor for special testing to determine what you are allergic to.


Home care

If was safe for you to go home, watch for any worsening of symptoms. You may need to be treated again.


Injectable epinephrine

One of the key tools in treating anaphylaxis is early use of epinephrine. If you had a severe allergic or anaphylactic reaction, the doctor may prescribe a self- injectable epinephrine kit. If this was prescribed, carry it at all times. It can be life saving. Epinephrine can help stop the progression of an allergic reaction. Its effects are brief, so after you use the medicine,  it is still very  important to call 911 and get to an emergency room.

When to use injectable epinephrine. Use the epinephrine if you have a history of severe reactions or any of the following symptoms:

  • Swelling in your mouth or throat 

  • Trouble speaking or swallowing

  • Trouble breathing

  • Feeling faint, low blood pressure, or becoming drowsy or poorly responsive

  • Worsening rash

How to use injectable epinephrine:

  • Hold the syringe firmly in your hand with the orange (or black) needle end away from your thumb

  • Be careful not to stick your fingers or hand with the needle!

  • At the opposite end, pull off the activation cap- the blue or grey tab

  • Holding the syringe tightly, jab it into the outer part of your upper thigh. This is one of the softest, fleshiest parts of the upper leg, and is not near a major blood vessel or nerve. Be careful not to inject it into your hip or any place that there is a pulse.

  • You can inject it through pants, but make sure not to inject it into the seam of the pants.

  • Do not pull it out right away. Try to hold the needle in place for 10 seconds.

  • Massage the spot for a few seconds.

  • If you are injecting it in someone else or a child, try to hold them or their leg still. If they jerk or yank their legs away as you are doing it, it can cause a cut on their leg.

You may feel shaky, jittery, nervous, and anxious after the injection. Although it is difficult, try to relax. This is a side effect of the epinephrine, and should stop after a few minutes 


  • Get to the emergency room after using the epinephrine. Its affect will wear off, and you may have a second reaction. This could even happen hours later.

  • Never intentionally eat, use, or expose yourself to the substance that caused the anaphylactic reaction.  Nothing is foolproof, including the injectable epinephrine.

Other medications

The doctor may prescribe medicine to relieve swelling, itching, and pain. Follow the doctor’s instructions when this medicine. 

  • Oral Benadryl (diphenhydramine) is an antihistamine available at drug and grocery stores. Unless a prescription antihistamine was given, Benadryl may be used to reduce itching if large areas of the skin are involved. It may make you sleepy, so be careful using it in the daytime or when going to school, working, or driving. 

  • Do not use Benadryl cream on your skin, because in some people it can cause a further reaction, and make you allergic to Benadryl.

  • You may use over-the-counter acetaminophen or ibuprofen to control pain, unless another pain medicine was prescribed.

  • If you were prescribed any medicines to prevent symptoms from returning, be sure to take them exactly as directed.

General care

  • Rest at home for the next 24 hours.

  • Avoid tobacco and alcohol consumption. These may worsen your symptoms.

  • If you know what caused your reaction today, avoid that in the future since the next reaction may be worse. Let your family members, friends and personal physician know about your allergic reaction.

  • If your allergy was to food, learn how to read food labels so you can check for that ingredient. If a product does not have a label, it is best to avoid it.

  • Consider carrying an identification card or getting a medical alert bracelet to inform medical personnel of your condition in case you cannot tell them.

  • Tell all of  your healthcare providers know you had an anphylactic reaction.  Make certain the information is added to your electronic or paper medical records.

Follow-up care

Follow up with your doctor or as advised if you are not improving over the next 1 to 2 days.

Call 911

Call 911 if any of these occur:

  • Trouble breathing or swallowing, wheezing

  • Hoarse voice or trouble speaking

  • Chest pain

  • Confused

  • Very drowsy or trouble awakening

  • Fainting or loss of consciousness

  • Rapid heart rate

  • Vomiting blood, or large amounts of blood in stool

  • Seizure

When to seek medical advice

Call your healthcare provider right away if any of these occur:

  • Worsening of your symptoms

  • Swelling in the mouth or face

  • Dizziness, weakness

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