Anaphylaxis is a severe, sometimes life-threatening, allergic reaction. It affects multiple organs, including the heart and lungs.
It is important to seek emergency medical care right away if you have symptoms of anaphylaxis.
Substances that cause anaphylaxis are often called allergens or triggers. Common triggers include:
Some triggers, like dyes used in x-ray procedures, can cause a reaction similar to anaphylaxis.
Anyone can have anaphylaxis. Factors that may increase your risk of anaphylaxis include:
The symptoms of anaphylaxis usually occur within minutes after exposure to an allergen, but can occur hours later. Symptoms may be mild or severe, including death. They include:
The diagnosis of allergy with a risk of anaphylactic reactions is made based on the patient’s history. Anaphylaxis will be suspected if you have symptoms and have been exposed to a likely allergen. It is important to see a doctor who specializes in allergies (allergist/immunologist). Skin tests and sometimes blood tests can done by allergy specialists to confirm the cause of the reaction.
Anaphylaxis is a medical emergency that requires immediate medical treatment, including:
Note: If you receive emergency epinephrine, you should go to the emergency room right away, even if your symptoms have gone away.
Avoiding substances that trigger anaphylaxis is the best prevention. In addition:
American Academy of Allergy, Asthma, and Immunology
Food Allergy Research and Education
Allergy Asthma Information Association
Calgary Allergy Network
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Last reviewed September 2015 by Marcin Chwistek, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.