Angioedema is localized deep swelling of one or several areas of the body. Because of the size and type of swelling, angioedema is sometimes called “giant hives.”
It is often caused by a reaction to an allergen or medication. Some medications that commonly cause angioedema include ACE inhibitors (treatment for high blood pressure) and nonsteroidal anti-inflammatory drugs (NSAIDS), such as ibuprofen or aspirin, used to treat pain.
Angioedema also may occur in connection with another illness, such as an autoimmune disease, or infection. Some people have idiopathic angioedema, meaning that there is no known cause. There also is a rare, more serious, form of angioedema that runs in families, called hereditary angioedema.
Angioedema is different from other common causes of edema (swelling) in several ways.
Angioedema is rapid in onset (minutes to hours) instead of a gradual onset over days to weeks.
Angioedema is often asymmetric. This means it is not balanced, and the swelling can change shape.
Angioedema can involve different parts of the body, including the throat, lips, face, genital region, hands, feet and/or internal organs, such as the intestines. It can also affect the airways and cause difficulty in breathing.
Most other causes of edema affect mainly areas of the body that are “dependent,” such as the lower legs and ankles, due to the effects of gravity. Angioedema doesn’t tend to do this.
Angioedema is often, but not always, accompanied by hives and can even be part of anaphylaxis, which is a full-body allergic reaction.
The symptoms of angioedema range from mild to extremely serious and even life-threatening. Most often, it is not serious, and sometimes even goes away without treatment. However, it also can be life-threatening when it affects the airway. Angioedema should always be taken seriously.