ACE inhibitors are medications that are used for hypertension, kidney disease, diabetes and heart disease patients. Some examples of ACE inhibitors (-pril medications) are ramipril, enalapril, captopril, and perindopril. ACE inhibitors act to lower blood pressure by inhibiting angiotensin converting enzyme, which is an enzyme that converts angiotensin I into angiotensin II. Angiotensin II is a potent vasoconstrictor, but it does have a variety of other affects as well. This video discusses the minor and mild side effects and very serious, life-threatening side effects of using ACE inhibitors.