this is angioneurotic oedema (or angioedema), a form of localised swelling of the deeper layers of the skin and fatty tissues beneath the skin. Hereditary angioneurotic oedema (or hereditary angioedema) is a genetic form of angioedema. Persons with it are born lacking an inhibitor protein (called C1 esterase inhibitor) that normally prevents activation of a cascade of proteins leading to the swelling of angioedema. Patients can develop recurrent attacks of swollen tissues, pain in the abdomen, and swelling of the voice Box (larynx) which can compromise breathing. The diagnosis is suspected with a history of recurrent angioedema. It is confirmed by finding abnormally low levels of C1 esterase inhibitor in the blood. Treatment options include antihistamines and male steroids (androgens) that can also prevent the recurrent attacks.