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Emergency Department Discharge Instructions

Allergic reaction

Emergency Care Discharge Instructions

Instruction summary

An allergic reaction occurs when your body’s defense system fights substances that are usually harmless (such as pollen or certain foods) as though these substances were harmful. Often the emergency physician cannot tell you what caused the reaction. If it was severe, do follow-up with your family physician, who can send you to an allergy specialist for allergy testing. Allergy testing can help you determine what you are allergic to so that you can avoid it in the future.

The usual treatment for an allergic reaction is the over-the-counter medication called Benadryl (generic name: “Diphenhydramine”). Adults should take 50 mg of Benadryl every six hours for 48 hours (i.e. four times per day, for two days). It is important to take this medication for the full two days because some allergic reactions go away but then return at 48 hours. If the medication makes you drowsy, you can replace the two daytime doses with a non-drowsy allergy medication, such as Extra-Strength Reactine. Avoid driving or operating heavy machinery when taking Benadryl.

Steroid medication is sometimes used as well, such as Prednisone. Prednisone may temporarily affect your blood sugar and make you feel moody, but it is very effective at treating the allergic reaction and should be taken as prescribed. If you have trouble sleeping when taking it, try taking it in the morning, instead of later in the day. If you have been given a prescription of an EpiPen make sure that you fill this prescription: it could save your life. Use the EpiPen as directed in the kit, particularly if you have any of the following symptoms:

  1. Any swelling in your lips, tongue, or throat
  2. Difficulty breathing or abnormal breathing sounds
  3. Feeling light-headed or faint

If you have any of these symptoms, do not be afraid to use your EpiPen immediately. It will not harm you to take it, and it may save your life. After using it, go immediately to the ER. The EpiPen gives you ≈ 30 minutes in which to call an ambulance and get to the ER.