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Last full review/revision Jan 2021| Content last modified Jan 2021
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What is angioedema?

  • The swelling may get so bad that you can't breathe

  • Angioedema can start suddenly and come and go for weeks or months depending on the cause

  • Doctors may give you epinephrine and antihistamines to lessen your symptoms

Go to the emergency room if you have swelling of your face or throat.

What causes angioedema?

Angioedema may be your body’s reaction to:

  • Medicine, particularly a type of blood pressure medicine called an ACE inhibitor

  • Insect stings or bites

  • Allergy shots

  • Food, such as eggs, fish, nuts, and fruit

What are the symptoms of angioedema?

Angioedema usually causes swelling in your face, lips, and tongue. Sometimes the inside of your mouth and throat swell up, making it hard to swallow or breathe. Your voice may sound hoarse.

Along with the swelling, you may also have these symptoms:

  • Hives that come and go (red, itchy, raised patches on the skin)

  • Feeling sick to your stomach, throwing up, or belly cramps

How can doctors tell if I have angioedema?

Doctors can tell based on your symptoms and by examining you. If doctors can’t find the cause, they’ll ask you questions, have you stop taking medicines you might be allergic to, and may do tests.

How do doctors treat angioedema?

The most important thing is to keep your breathing passages open. If you're having trouble breathing, doctors may:

  • Put a breathing tube down your throat

  • Give you a shot of epinephrine

Other treatments depend on what doctors think caused your angioedema. Doctors may give you:

  • Antihistamines to lessen itching and swelling

  • Corticosteroids

If you have hereditary angioedema, there are special medicines doctors may give you by vein (IV).

Avoiding the cause of your angioedema can help prevent it in the future. If you have a severe reaction, you should always carry a shot of epinephrine and antihistamine pills with you to take in case you start to have another reaction. Then go to a hospital emergency room in case you need more treatment.

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