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Anaphylactic Reaction: Care Instructions

Your Care Instructions

A bad allergic reaction can affect your whole body. Doctors call it an anaphylactic reaction. Your immune system may have reacted to food or medicine. Or maybe you had an insect bite or sting. This kind of reaction can happen the first time you come into contact with a substance. Or it may take many times before a substance causes a problem.

You need to get help right away if your body reacts like this again.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse advice line (811 in most provinces and territories) if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.

How can you care for yourself at home?

  • If your doctor has prescribed medicine, such as an antihistamine, take it exactly as directed. Call your doctor or nurse advice line if you think you are having a problem with your medicine.
  • Learn all you can about your allergies. You may be able to avoid a severe response when you do or don't do certain things. For instance, you can check food or drug labels for contents that might cause problems.
  • Your doctor may prescribe a shot of epinephrine to carry with you in case you have a severe reaction. Learn how to give yourself the shot. Keep it with you at all times. Make sure it has not expired.
  • Wear medical alert jewellery that lists your allergies.
  • Teach people around you about your allergies. Tell them what you need to avoid. Teach them what to do if you have a reaction.
  • Before you take any medicine, tell your doctor if you have had a bad response to any medicines in the past.

When should you call for help?

Give an epinephrine shot if:

  • You think you are having a severe allergic reaction.
  • You have symptoms in more than one body area, such as mild nausea and an itchy mouth.

After giving an epinephrine shot, call 911 even if you feel better.

Call 911 if:

  • You have symptoms of a severe allergic reaction. These may include:
    • Sudden raised, red areas (hives) all over your body.
    • Swelling of the throat, mouth, lips, or tongue.
    • Trouble breathing.
    • Passing out (losing consciousness). Or you may feel very light-headed or suddenly feel weak, confused, or restless.
    • Severe belly pain, nausea, vomiting, or diarrhea.
  • You have been given an epinephrine shot, even if you feel better.

Call your doctor or nurse advice line now or seek immediate medical care if:

  • You have symptoms of an allergic reaction, such as:
    • A rash or hives.
    • Itching.
    • Swelling.
    • Mild belly pain or nausea.

Watch closely for changes in your health, and be sure to contact your doctor or nurse advice line if:

  • You do not get better as expected.

Where can you learn more?

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Care instructions adapted under license by your healthcare professional. If you have questions about a medical condition or this instruction, always ask your healthcare professional. Healthwise, Incorporated disclaims any warranty or liability for your use of this information.