ACE inhibitors are a group of medicines that are mainly used to treat certain heart and kidney conditions; however, they may be used in the management of other conditions such as migraine and scleroderma.
They block the production of angiotensin II, a substance that narrows blood vessels and releases hormones such as aldosterone and norepinephrine, by inhibiting an enzyme called angiotensin converting enzyme. Angiotensin II, aldosterone, and norepinephrine all increase blood pressure and urine production by the kidneys. If levels of these three substances decrease in the body, this allows blood vessels to relax and dilate (widen), reducing both blood and kidney pressure.

ACE inhibitors used for:

• Certain chronic kidney conditions (but not others)
• Coronary artery disease