Among the most recognized examples of adverse side effects afforded by ACE inhibitors are cough (experienced by 5–20% of patients) and angioedema (experienced by 0.1–0.5% of patients), both of which are associated with elevated levels of bradykinin and substance P in patients taking these drugs (Byrd et al., 2006; Israili & Hall, 1992). This evidence concerns the gene ACE and angioedema.