Angiotensin-converting enzyme (ACE) inhibitors are a remarkable class of drugs for treating
hypertension – high blood pressure. These drugs work by interfering with the enzymes that convert an inactive chemical known as
angiotensin I to an active form,
angiotensin II. Angiotensin II increases the retention of salt and water in the body, raising blood pressure. ACE inhibitors interfere with, or inhibit, the formation of angiotensin II, resulting in relaxed arterial walls and lowered blood pressure.
Since the release of the first ACE inhibitor in the 1980s, known generically as
captopril, there are now several different ACE inhibitors available on the market. Many of them are also available in combination with other types of hypertension medications, such as
diuretics.
ACE inhibitors have achieved astounding popularity because they are markedly effective and cause few side effects. Some people do experience a chronic cough that is bad enough in some cases to cause them to quit taking ACE inhibitors. Others may develop
angioedema, which can cause severe swelling of the face, tongue, vocal cords, and extremities. ACE inhibitors also elevate potassium levels in the body, and they are not approved for use during pregnancy.
Besides lowering blood pressure, ACE inhibitors have become one of the best treatments for heart failure. Other uses for this drug, such as therapy for heart attacks and diabetes mellitus, are under study.
