How Is an Allergic Reaction Diagnos

How Is an Allergic Reaction Diagnosed?
Allergic reactions can be diagnosed by your doctor. If you experience symptoms of an allergic reaction, your doctor will perform an exam and ask you about your health history. If your allergic reactions are severe, your doctor may ask you to keep a journal that details your symptoms and what substances appear to cause them. Your doctor may want to order tests to determine what is causing your allergy. The most common types of allergy tests are:
• skin tests
• challenge (elimination-type) tests
• blood tests
A skin test involves applying a small amount of a suspected allergen to the skin and watching for a reaction. The substance may be taped to the skin (patch test), applied to a small prick in the skin (prick test), or injected just under the skin (intradermal test). A skin test is most valuable for diagnosing:
• food allergy
• mold, pollen, and animal dander allergy
• penicillin allergy
• venom allergy (such as mosquito bites or bee stings)
• allergic contact dermatitis (a rash you get from touching a substance)
Challenge testing is useful in diagnosing food allergies. It involves removing a food from your diet for several weeks and watching for symptoms when you eat the food again.
A blood test for an allergy checks your blood for antibodies against a possible allergen. An antibody is a protein your body produces to fight harmful substances. Blood tests are used when skin testing is not helpful or cannot be done.

How Is an Allergic Reaction Treated?
If you experience an allergic reaction and you do not know what is causing it, you may need to see your doctor to determine what you are allergic to. If you have a known allergy and experience symptoms, you may not need to seek medical care if your symptoms are mild. In most cases, over-the-counter antihistamines, such as Benadryl, can be effective for controlling mild allergic reactions.
If you or someone you know experiences a severe allergic reaction, you should seek emergency medical attention. Check to see if the person is breathing, call 911, and provide cardiopulmonary resuscitation (CPR) if needed. People with known allergies often have emergency medications with them such as an EpiPen, which injects the drug epinephrine. Epinephrine opens the airways and raises blood pressure. This is called a rescue drug. If the person is unable to administer the medication, help him or her to take it. If the person is unconscious, you should:
• lay the person flat on his or her back
• elevate the person’s legs
• cover the person with a blanket
This will help prevent shock.

How Can You Prevent an Allergic Reaction?
You may not be able to prevent an allergic reaction. But there are steps that you can take to prevent future allergic reactions. Once you identify your allergy you can:
• avoid exposure to the allergen
• seek medical care if you are exposed to the allergen
• carry medications to treat anaphylaxis