What condition is indicated by localized swelling due to blood vessel leakage from allergic reactions?

Localized swelling due to blood vessel leakage from allergic reactions is characterized as angioedema. This condition involves deeper layers of the skin and subcutaneous tissues, leading to pronounced swelling, often around the eyes, lips, and sometimes in the throat. Angioedema typically results from the release of histamines and other substances during an allergic reaction, which increases the permeability of blood vessels, causing fluid to leak into the surrounding tissues.

Urticaria, commonly known as hives, may also be related to allergic reactions and involves raised welts on the skin with itching but does not specifically refer to deeper swelling as angioedema does. Rosacea is primarily a chronic inflammatory condition affecting the face, characterized by redness and visible blood vessels, without the acute localized swelling seen in angioedema. Contact dermatitis, while it can cause reactions due to allergens or irritants, typically presents with a rash and inflammation on the surface of the skin rather than the deeper swelling associated with angioedema.