Table of Contents
ACE inhibitors, also known as angiotensin-converting enzyme inhibitors, are a class of medications primarily used to treat hypertension and heart failure. They work by interfering with the body’s renin-angiotensin system, which plays a crucial role in regulating blood pressure and fluid balance.
What Are ACE Inhibitors?
ACE inhibitors block the enzyme responsible for converting angiotensin I to angiotensin II, a potent vasoconstrictor. By inhibiting this enzyme, these drugs help relax blood vessels, reduce blood pressure, and decrease the workload on the heart.
Major Classes of ACE Inhibitors
- Short-acting ACE inhibitors
- Long-acting ACE inhibitors
These classes differ mainly in their duration of action, influencing dosing schedules and clinical use.
Examples of ACE Inhibitors
- Enalapril
- Lisinopril
- Captopril
- Ramipril
- Fosinopril
Mechanisms of Action
ACE inhibitors prevent the formation of angiotensin II, leading to vasodilation. They also decrease aldosterone secretion, reducing sodium and water retention. These combined effects lower blood pressure and decrease cardiac strain.
Vasodilation
By inhibiting angiotensin II, ACE inhibitors cause blood vessels to relax and widen, which lowers systemic vascular resistance.
Aldosterone Suppression
Reduced aldosterone levels lead to decreased sodium and water retention, further helping to lower blood volume and pressure.
Clinical Uses
- Hypertension management
- Heart failure treatment
- Prevention of stroke
- Diabetic nephropathy
Side Effects and Precautions
- Cough
- Hyperkalemia
- Hypotension
- Angioedema
Patients with certain conditions, such as bilateral renal artery stenosis or pregnancy, should use ACE inhibitors with caution. Regular monitoring of kidney function and electrolytes is recommended during therapy.