ACI drugs, or Angiotensin-Converting Enzyme (ACE) inhibitors, are medications used to lower blood pressure and protect the heart. They work by blocking the production of angiotensin II, a substance that narrows blood vessels.
How ACE Inhibitors Work
Angiotensin-converting enzyme (ACE) inhibitors work by targeting the renin-angiotensin-aldosterone system (RAAS), a hormone system that regulates blood pressure and fluid balance. Specifically, they:
- Inhibit ACE: ACE is an enzyme that converts angiotensin I to angiotensin II.
- Reduce Angiotensin II: By inhibiting ACE, these drugs reduce the production of angiotensin II, a potent vasoconstrictor (a substance that narrows blood vessels).
- Vasodilation: Lower levels of angiotensin II cause blood vessels to relax and widen (vasodilation), lowering blood pressure.
- Reduce Aldosterone: Angiotensin II also stimulates the release of aldosterone, a hormone that causes the kidneys to retain sodium and water. ACE inhibitors reduce aldosterone levels, further contributing to lower blood pressure.
Common Uses of ACE Inhibitors
ACE inhibitors are commonly prescribed for:
- High Blood Pressure (Hypertension): By relaxing blood vessels, ACE inhibitors effectively lower blood pressure.
- Heart Failure: They help the heart pump blood more efficiently.
- Kidney Disease (Diabetic Nephropathy): They can protect the kidneys in people with diabetes.
- After a Heart Attack: They can improve survival and prevent future heart problems.
Examples of ACE Inhibitors
Some common examples of ACE inhibitors include:
- Enalapril (Vasotec)
- Lisinopril (Prinivil, Zestril)
- Captopril (Capoten)
- Ramipril (Altace)
- Benazepril (Lotensin)
Potential Side Effects
While generally safe, ACE inhibitors can cause some side effects, including:
- Dry Cough: This is a common side effect due to increased bradykinin levels.
- Dizziness: Caused by lowered blood pressure.
- Fatigue: A general feeling of tiredness.
- Kidney Problems: Requires monitoring of kidney function.
- Angioedema: A rare but serious allergic reaction that causes swelling of the face, tongue, or throat.
Important Considerations
- Pregnancy: ACE inhibitors should not be used during pregnancy due to the risk of birth defects.
- Potassium Levels: They can increase potassium levels, so monitoring is important, especially in people with kidney problems.
- Drug Interactions: They can interact with other medications, such as NSAIDs and diuretics.
ACE inhibitors are a valuable class of drugs for managing high blood pressure and protecting the cardiovascular system by relaxing blood vessels, which reduces the strain on the heart.
