ACE inhibitors are a first-line treatment for high blood pressure and are also added in to other classes of blood pressure treatment if the single drug alone does not control blood pressure. Examples of an ACE inhibitor drug include captopril, enalapril, fosinopril, imidapril, lisinopril, perindopril, quinapril, ramipril and trandolapril.
How ACE inhibitors lower blood pressure
ACE inhibitors get their name because they block the action of an enzyme (angiotensin converting enzyme, or ACE). This action prevents the formation of a substance called angiotensin II which causes arteries to constrict. By blocking its formation, ACE inhibitors cause your small arteries and veins can dilate so your blood pressure falls.
Dilation of blood vessels supplying the kidneys also increases the amount of fluid and sodium lost as urine for a further beneficial effect on blood pressure.
On average, an ACE inhibitor reduces systolic blood pressure (your upper reading) by 6.8 mmHg when used alone.
Kidney function and salt balance should be checked before treatment is started. Low doses are used initially as ACE inhibitors can cause a sudden fall in BP. Their most troublesome side effect is a dry cough.
Patient information leaflets
To find out more about the most common ACE inhibitors, including their possible side effects, click on the following links. These will take you to a typical Patient Information Leaflet that is found inside a UK pack of these medicines. Always read the patient information leaflet supplied with your own medicine as different preparations vary.
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