Allergies Health Center

Understanding Anaphylaxis -- Diagnosis & Treatment

How Is Anaphylaxis Diagnosed?

Anaphylaxis is diagnosed on the basis of its signs and symptoms. A history of exposure to an allergen can also be helpful.

It is difficult to gauge an individual's potential for a severe allergic response before it occurs. However, those with a history of allergic reactions -- mild, moderate, or severe -- may be at greater risk of having a severe reaction in the future.

Tests that are commonly used to assess allergic responses include skin-prick or scratch tests, intradermal skin tests and blood tests that can identify specific antibodies that indicate particular allergies. Skin-prick or scratch testing involves placing a small drop of allergen on the skin and scratching with it without breaking the skin surface. Intradermal, or percutaneous testing, involves placing small amounts of suspected allergens under the skin and watching for signs of allergic reaction. 

What Are the Treatments for Anaphylaxis?

Epinephrine is the most effective immediate treatment for anaphylaxis. It rapidly reverses the uncomfortable flushing and itching as well as the more serious problems with breathing and dangerous drop in blood pressure that accompanies most anaphylactic reactions. More importantly, if given in time, epinephrine can reverse the life-threatening symptoms of anaphylactic shock. If you are allergic to insect stings or any of the foods that cause anaphylaxis, or if you ever have had an anaphylactic reaction, you should contact your physician about providing an epinephrine injection kit. (Epi-Pen is one common brand name.) You should carry it at all times and know how to use it. If you're at risk, make sure your family members, friends, and colleagues know the signs of anaphylaxis and how to give you an injection if needed.

If someone appears to be suffering from anaphylaxis, call for emergency help, even if the person has already been given an epinephrine injection. The person may require additional doses or other medical interventions. Anyone who has an anaphylactic reaction should be checked by medical personnel. After getting epinephrine, steroid drugs (such as prednisone or methylprednisolone) and antihistamines (given after epinephrine) can also help to calm hives and itching and prevent the return of acute symptoms.

If a victim of anaphylaxis stops breathing, perform cardiopulmonary resuscitation (CPR) immediately. Continue CPR until the person begins breathing again or emergency medical personnel take over.

Certain medicines, such as beta-blockers (often given for high blood pressure) and angiotensin-converting enzyme (ACE) inhibitors (often given for heart disease), may hinder the successful treatment of an anaphylactic reaction. If you ever have suffered a severe allergic reaction and are taking either of these drugs, ask your doctor whether your medication should be changed.