The investigators will test the hypothesis that treatment with fresh frozen plasma that contains high levels of ACE activity will increase serum ACE activity and thereby cause the degradation of mediators of ACE inhibitor-induced angioedema, such as bradykinin and substance P, resulting in a shortening of the course of ACE inhibitor-induced angioedema.~16 patients with ACE inhibitor-induced angioedema will be randomized 1:1 to treatment with either 2 units of fresh frozen plasma that has been preselected for high ACE activity content (≥50 U/L) or an equal volume of normal saline. A baseline assessment of the severity of the angioedema will be performed and baseline serum levels of ACE activity will be determined. The severity of angioedema will be assessed and serum levels of ACE activity will be determined at specific intervals after each subject is treated.
Angiotensin Converting Enzyme (ACE) inhibitors are among the most important and widely prescribed drugs. They reduce the morbidity and mortality associated with high blood pressure, heart disease, and kidney disease. Unfortunately, their use carries the risk of causing life-threatening airway swelling in some patients. There is currently no treatment for this condition. A novel treatment approach that may reduce or completely reverse the swelling will be tested.