What is hereditary angioedema (HAE)?
HAE is a rare genetic condition characterized by unpredictable swelling. It can be life-threatening if the swelling blocks airways and prevents breathing.
When you have HAE Type I or II, a gene called SERPING1, which makes the C1-INH protein (C1-inhibitor), is either not making enough protein (Type I) or is not working correctly (Type II). This protein is important in controlling certain types of swelling in the body.
Having not enough C1-INH protein in your body can cause HAE symptoms like: