angioedema an·gi·o·e·de·ma (ān'jē-ō-ĭ-dē'mə)
See angioneurotic edema.
allergic disorder in which large, localized, painless swellings similar to hives appear under the skin. The swelling is caused by massive accumulation of fluid (edema) following exposure to an allergen (a substance to which the person has been sensitized) or, in cases with a hereditary disposition, after infection or injury. The reaction appears suddenly and persists for a few hours or days, occurring most often on the face, hands, feet, genitals, and mucous membranes.
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