We are very familiar with the term of Angioedema. Mostly comes from ACE-In but has a large ddx from NSAIDS to hereditary to idiopathic. There is an article in Academic EM that is discussing the treatment options for Angioedema. They categorize Angioedema to histaminergic-mediated vs Bradykini-meiated. In ED usually we do not know the underline disease of patient . we may find with history that patient has hereditary angioedema(HAE), but we can not diagnose the pathology in an acute setting specifically with a patient with airway concern. I recommend you to read this article in AEM.