Angioedema: an overview and update.

Angioedema is an increasing cause of hospitalizations in the United States. This syndrome presents with non-pitting, asymmetric swelling of the face, lips, tongue, larynx, genitalia, and extremities, although any part of the body can be involved. Common causes of angioedema include allergic reactions and ACE inhibitors. Hereditary angioedema is a rare form of angioedema that can be diagnosed by screening with a C4 level. In 2009, three new treatments for hereditary angioedema were approved for use in the United States, revolutionizing management of this rare disease.