What is HAE?

HAE is the result of a genetic mutation caused by a deficiency of the blood protein functional C1 esterase inhibitor (C1-INH). Patients with HAE suffer from repeated episodes of spontaneous swelling that can occur at any time and in almost any part of the body but more predominantly in the hands, feet, face, airway (throat) and internal organs. HAE is not an allergy or allergic reaction.