[1]: 120 Angioedema presents itself as an abrupt onset of non-pitting, non-itchy swelling that involves the mucosal layers.
Some common locations of angioedema are the face, particularly the lips and around the eyes, hands and feet, and genitalia.
[2] A rare, yet serious complication is one inside the abdomen, the symptom usually being severe stomach upset, which is much less obvious than the other locations.
[4] The reason this adverse effect may occur is due to the build-up of bradykinin, a vasodilator.
Angiotensin-Neprilysin Inhibition versus Enalapril in Heart Failure (PARADIGM-HF Investigators); NEJM.org, September 11, 2014; Vol.371, No.11.