ACE inhibitors are widely prescribed for the treatment of high blood pressure (hypertension) as well as certain forms of heart failure, and immediately after a heart attack. These medications may be administered in the form of a tablet, capsule, liquid or intravenous (IV) injection. They generally begin to affect the body within one to two hours after being taken by mouth (i.e., tablet, capsule or liquid) and almost instantly after injection.

People taking ACE inhibitors are encouraged to drink sufficient liquids during exercise or while outside in hot weather. Physician’s orders about exercise, activity levels and diet should also be followed exactly. People taking ACE inhibitors should also consult their physicians before taking NSAIDs (nonsteroidal anti-inflammatory drugs). In addition, anyone taking ACE inhibitors or any other antihypertensives need to be careful about spending too much time in the heat.

The most common side effect of ACE inhibitors is coughing, which is usually not serious but may occur in up to 20 percent of patients. In some cases, this side effect will cause the physician to prescribe a different antihypertensive. Regular blood tests are needed to screen for a potentially serious side effect called hyperkalemia – an abnormally high level of potassium in the blood.