Conventional medicine defines this as recurring swelling that happens for no known reason. I have this and I know several triggers for me including food sensitivities, chemical sensitivities, seasonal allergies, any mild physical trauma like burning my tongue on hot food or nicking myself shaving, and stress. I've had issues since childhood and I have never been on ACE inhibitors. Antihistamines including H1 and H2 blockers don't work for me. I'm on a biologic shot called Xolair that is an IgE binder that does work for me.
I'm APOE4/4 and with the 4/4 being pro-inflammatory, I was wondering if there could be a link.