Idiopathic non-histaminergic angioedema may respond to a variety of medications, including steroids, dapsone, rituximab, icatibant (a bradykinin receptor antagonist), ecallantide (a kallikrein inhibitor), C1 esterase inhibitor concentrate, tranexamic acid, cannabis and omalizumab [6–13]. The gene discussed is KLK4; the disease is angioedema.