ACEinhibitory

ACE inhibitors are a class of medications that inhibit the angiotensin-converting enzyme (ACE), which normally converts angiotensin I to angiotensin II and degrades bradykinin. By lowering angiotensin II levels and increasing bradykinin, these drugs produce vasodilation of both arteries and veins, decrease aldosterone secretion, and reduce the work of the heart. The overall effect is lowered blood pressure, reduced afterload, and often improved renal blood flow. They can also help slow structural remodeling after myocardial injury and may protect renal function in conditions such as diabetic nephropathy, though creatinine and potassium should be monitored.

They are used to treat hypertension, heart failure with reduced ejection fraction, and to improve survival after myocardial infarction. They are also employed in certain chronic kidney diseases and in patients with diabetes or proteinuric kidney disease. They are generally avoided during pregnancy due to fetal risks and used with caution in bilateral renal artery stenosis and in patients with significant renal impairment.

Most ACE inhibitors are given orally and vary in duration of action. Some are prodrugs requiring hepatic activation, while others are active in their administered form. Common agents include captopril, enalapril, lisinopril, ramipril, benazepril, and others. They are often dosed once or twice daily, with adjustments for renal function. Potential drug interactions include potassium-sparing diuretics, NSAIDs, and certain salts, which can affect efficacy or safety.

Common adverse effects include cough, dizziness, hyperkalemia, and hypotension. Angioedema is a rare but serious risk, more prominent in some populations. Contraindications include pregnancy and bilateral renal artery stenosis. Monitoring of blood pressure, creatinine, and potassium is recommended during therapy.