Mast cell-mediated angioedema Tends to develop over minutes to several hours May be accompanied by other manifestations of acute allergic reactions (eg, pruritus, urticaria, flushing, bronchospasm, anaphylactic shock) Bradykinin-mediated angioedema Tends to develop over hours to a few days Is not accompanied by other manifestations of allergic reactions Diagnosis of Angioedema Clinical evaluation For diagnosis of urticaria, see Urticaria: Evaluation.