Angiotensin-conveing enzyme (ACE) inhibitors block production of the hormone, angiotensin II, a compound in the blood that causes narrowing of blood vessels and increases blood pressure. By reducing production of angiotensin II, ACE inhibitors allow blood vessels to widen, which lowers blood pressure and improves hea output. The available ACE inhibitors include benazepril, captopril, enalapril, fosinopril, lisinopril, moexipril, perindopril, quinapril, ramipril, and trandolapril. Side effects -- In some patients, ACE inhibitors cause a persistent dry hacking cough that is reversible when the medication is stopped. Less common side effects include dry mouth, nausea, rash, muscle pain, or occasionally, kidney dysfunction and elevated blood potassium. A potentially serious complication of ACE inhibitors is angioedema, which occurs in 0.1 to 0.7 percent of people. People with angioedema rapidly (minutes to hours after taking the medication) develop swelling of the lips, tongue, and throat, which can interfere with breathing. These symptoms are a medical emergency, and the ACE inhibitor should be discontinued. oral enalapril may also be used in young hypeensives who presents with ususually high levels of blood pressure to overcome the end stage damages that can happen. ref:Harrison&;s principles of internal medicine,ed 18,pg no 2057