An ACE inhibitor is any of a group of vasodilators, introduced in 1981. ACE (angiotensin-converting enzyme) inhibitors are used to treat high blood pressure (hypertension) and heart failure (reduced pumping efficiency). They are often prescribed with other drugs, for example, diuretics (water pills) or beta blockers
How ACE inhibitors work
ACE inhibitor drugs block the action of the enzyme that converts angiotensin (a protein present in the blood) from an inactive form, angiotensin I, to an active form, angiotensin II, which constricts blood vessels. By reducing production of angiotensin II, ACE inhibitors reduce constriction of blood vessels, which makes it easier for the blood to flow through them, and thus reduces blood pressure.
Possible adverse effects
These include nausea, loss of taste, headache, dizziness, and a dry cough. The most common side effect associated with an ACE inhibitor is hypotension (low blood pressure). In fact, the first dose may reduce blood pressure so dramatically that the patient collapses; treatment is often therefore often stated in hospital.
A number of drugs may interact with ACE inhibitors. In particular, non-steroidal anti-inflammatory drugs (NSAIDs), diuretics, and lithium.