About Hereditary Angioedema

Hereditary angioedema (HAE) is a rare autoimmunological disease that is caused by a genetic defect and can be fatal if not treated appropriately.

Disease overview

Learn about 3 types of HAE, a debilitating, multisystem inherited disease caused by low or dysfunctional levels of plasma protein complement-1 esterase inhibitor (C1-INH).

Symptoms of HAE

HAE is characterized by acute, recurrent attacks of localized edema. Learn 8 simple questions to help with diagnosis.

Etiology and prevalence

HAE is a rare disorder, accounting for only 2% of clinical angioedema cases. According to the US Hereditary Angioedema Association (HAEA), epidemiologic studies place the worldwide incidence of HAE at approximately 1 in 10,000 to 50,000 persons. 9


Low levels of functional C1-INH in plasma lead to unregulated activation of the complement, contact and fibrinolytic systems and result in angioedema.