Angioedema is a well-known side effect of treatment with an angiotensin-converting enzyme (ACE) inhibitor and one that we have been willing to accept in view of the incidence of the problem and the clear benefits of this class of agents in numerous clinical situations. Angioedema is also seen with angiotensin receptor blocker (ARB) therapy but much less frequently than with ACE inhibitors. The mechanism for angioedema with ARB therapy remains poorly defined. ACE inhibitor-related angioedema occurs more commonly in black patients. The basis for an increased risk of angioedema in black patients remains unclear. Angioedema can be life-threatening but more times than not it can be managed with conservative treatment measures including specifically the discontinuation of the medication and/or administration of an antihistamine and/or epinephrine. Occasionally, maneuvers to protect the integrity of the airway may be needed. In a heart failure patient having previously experienced ACE inhibitor-related angioedema, ARBs should be used cautiously since angioedema has been reported with ARB therapy in heart failure patients. The need to reduce renin-angiotensin aldosterone system activity in a heart failure patient would seem to justify the small risk of angioedema with ARB therapy in a patient having previously experienced ACE inhibitor-related angioedema.