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Allergic Reaction: Care Instructions

Your Care Instructions

An allergic reaction is an excessive response from your immune system to a medicine, chemical, food, insect bite, or other substance. A reaction can range from mild to life-threatening. Some people have a mild rash, hives, and itching or stomach cramps. In severe reactions, swelling of your tongue and throat can close up your airway so that you cannot breathe.

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 you know what caused your allergic reaction, be sure to avoid it. Your allergy may become more severe each time you have a reaction.
  • Take an over-the-counter antihistamine, such as loratadine (Claritin), to treat mild symptoms. Read and follow all instructions on the label. Some antihistamines can make you feel sleepy. Do not give antihistamines to a child unless you have checked with your doctor first. Mild symptoms include sneezing or an itchy or runny nose; an itchy mouth; a few hives or mild itching; and mild nausea or stomach discomfort.
  • Do not scratch hives or a rash. Put a cold, moist towel on them or take cool baths to relieve itching. Put ice packs on hives, swelling, or insect stings for 10 to 15 minutes at a time. Put a thin cloth between the ice pack and your skin. Do not take hot baths or showers. They will make the itching worse.
  • 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 and keep it with you at all times. Make sure it is not expired.
  • Go to the emergency room every time you have a severe reaction, even if you have used your shot of epinephrine and are feeling better. Symptoms can come back after a shot.
  • Wear medical alert jewellery that lists your allergies.

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 (raised, red areas on the skin).
    • 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?

Go to https://www.healthwise.net/patientEd

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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.