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HAE patient Leah Weisbecker)

Hereditary Angioedema

Hereditary Angioedema

What is Hereditary Angioedema?

Hereditary Angioedema (HAE) is a rare hereditary disease that can cause attacks of swelling, and often pain, in specific parts of the body including the stomach, hands, feet, arms, legs, genitals, throat, and face. Depending on the severity of the disease, some people will have many attacks each month, while others will go months without an attack.

People with HAE are missing or have low levels of a protein called C1 esterase inhibitor (C1-INH); in some cases, the C1-INH levels are sufficient but the protein does not function properly. The defect with C1-INH lies within a person's genetic code, which is why HAE runs in families.

Types of HAE
Hereditary Angioedema is classified into three types based on what problem the genetic defect causes.

Type I - Low levels of C1-INH in the body; this is the most common form of HAE.
Type II - Normal levels of C1-INH, but it does not function normally; this accounts for ~15% of people with HAE.
Type III - Normal levels of C1-INH and it functions normally; this is extremely rare and not well understood.


  • 1 / 40,000 - 50,000

    people affected with HAE

  • 50%

    chance of someone with HAE passing it on to a child

  • 250+

    more than 250 different genetic mutations causing symptoms of HAE have been identified to date

Understanding HAE

What are the symptoms of HAE?

Answer 8 quick questions to see if your symptoms fit the profile of HAE.

What are the warning signs of an HAE attack?

HAE attacks can occur suddenly and without warning. However, many people notice symptoms at the very early stages of an attack, including sudden mood change, irritability, extreme fatigue, nausea, rash or tingling.