Sometimes these random attacks of swelling happen due to cold, heat, small injuries or even changes in emotions. A lot of the time they seem to happen for no known reason at all. This is why people with HAE should always carry their medicine, wear some sort of HAE identifying tag with them and participate in raising awareness about this rare disease.
Attacks can be set off by small trauma to the area, such as dental work, accidents, minor surgery, or tubes going down the throat (like for example during general anesthesia or camera scopes (endoscopies) for people who have stomach ulcers). Repeated activities like typing, gardening or construction work can trigger swellings. For some, standing for a long time can cause swelling on the bottom of the feet. The same goes for sitting for hours, where it can cause swelling of the buttocks. In women, menstruation and pregnancy seem to affect their attacks. In some, they have more attacks during their periods. Some have said that their attacks lessened during pregnancy. On the other hand, oral contraceptives and hormone replacement therapy is associated with an increase in the number of attacks and their severity.
Medicines normally used to treat high blood pressure, called ACE inhibitors, have been known to increase the frequency and intensity of HAE attacks. Hence, ACE inhibitors are to be avoided.
