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ACE Inhibitors - First Line Medication for Hypertension

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ACE inhibitors help to lower blood pressure. To know more about uses, dosage, interactions, warnings, and precautions read below.

Medically reviewed by

Dr. Muhammad Zohaib Siddiq

Published At November 23, 2022
Reviewed AtJanuary 22, 2024

What Are ACE Inhibitors?

Angiotensin-converting enzyme inhibitors (ACEIs) are commonly used medications to treat heart and blood vessel diseases. Angiotensin is produced by the body and helps in the contraction of the blood vessels, causing an increase in blood pressure. Angiotensin-converting enzyme inhibitors are medications that inhibit the activity of the ACE enzyme causing dilatation of the blood vessels and reduced blood pressure. This improves the functioning of the heart. ACE inhibitors have a synergistic effect and work well when prescribed with diuretics and calcium channel blockers.

Why Are ACE Inhibitors Used?

  • Hypertension - ACE Inhibitors are effective in treating cardiovascular conditions such as hypertension (high blood pressure), and coronary artery disease. The enzymes effectively lower the mean arterial blood pressure and blood pressure in hypertensive and normotensive patients.

  • Heart Failure - These inhibitors improve heart failure by decreasing afterload, preload, and systolic wall stress. ACE inhibitors reduce cardiac myocyte hypertrophy and are the first choice therapy in patients with heart failure.

  • Heart Attacks - ACE inhibitors are used to prevent heart attacks and stroke in people at high risk.

  • Diabetes - Treatment with ACE inhibitors in patients with left ventricular dysfunction reduces the progression to congestive heart failure after myocardial infarction. ACE inhibitors are the first-line therapy for hypertension with a history of diabetes. The use of ACE inhibitors decreases the incidence of myocardial infarction and improves heart function.

  • Proteinuria - Angiotensin-converting enzyme inhibitors provide protection against proteinuria and stabilize renal function in previously untreated patients.

  • Glomerular Disease - ACE inhibitors are the first line of treatment in managing chronic kidney disease and glomerular disease patients.

How Do ACE Inhibitors Work?

  • The ACE inhibitors block the angiotensin-converting enzyme from converting angiotensin I into angiotensin II. Angiotensin II stimulates the release of aldosterone and sodium absorption, thereby increasing blood volume and blood pressure.

  • The ACE inhibitors stimulate the dilation of blood vessels by inhibiting the production of angiotensin II. These inhibitory effects lead to increased sodium and urine excretion, increased venous capacity, and decreased cardiac output, stroke work, and volume.

  • ACE inhibitors also block the breakdown of bradykinin and cause a rise in protein and vasodilation of blood vessels.

How to Take ACE Inhibitors?

ACE inhibitors are commonly administered orally, except for Enalapril, which can be given intravenously. The ACE inhibitors are given without food. The ACE inhibitors should be taken in the amount recommended by the doctor and at the same time each day. It is advised to reduce salt substitutes while taking ACE inhibitors as they can cause potassium retention in the body. The medication works best when taken at bedtime. This is because they can reduce the effect of hormone that is most active during sleep. They are typically safe to be taken for long-term use. Therapy with ACE inhibitors should not be stopped without talking to the doctor. Always keep the medicine protected from heat, direct light, and moisture.

What Are the Various Types of ACE Inhibitors and Their Dosage?

ACE inhibitors can be effective for short-term and long-term treatments. Some of the common ACE inhibitors and their dosages include


What Are the Common and Serious Side Effects of ACE Inhibitors?

Side effects of ACE inhibitors may include

  • Dry cough.

  • Fatigue.

  • Dizziness from blood pressure going too low.

  • Headaches.

  • Loss of taste.

  • Itchy skin.

  • Angioedema.

  • Drowsiness.

  • Weakness.

Severe side effects include

  • Severe dry cough.

  • Swelling of face, eyes, mouth, lips, tongue, legs, or feet.

  • Jaundice.

  • Allergic reactions.

  • Increased potassium levels in the blood can be life-threatening. Signs of increased potassium levels in the body include confusion, difficulty breathing, irregular heartbeat, numbness or tingling in hands, feet, or lips.

Missed Dose:

If you miss a dose of an ACE inhibitor, it is advised to take the missed dose as soon as you remember. However, you should not double the dose as it can cause a severe, dangerous fall in blood pressure.

What Are the Interactions of ACE Inhibitors?

Interactions With Other Medicines:

  • Ibuprofen.

  • Naproxen.

  • NSAIDs (nonsteroidal anti-inflammatory drugs) such as Aspirin, Indomethacin.

  • Aliskiren.

  • Tetracycline.

  • Lithium.

Interaction With Food:

  • High Sodium Diet - Eating a diet high in salt can reduce the effectiveness of ACE inhibitors in lowering blood pressure.

  • Capsaicin - Taking capsaicin with food while taking ACE inhibitors can worsen the ACE inhibitor-related cough.

  • Food High in Potassium - Foods such as avocados, beetroot, oranges, potatoes, spinach, tomatoes, and tomato sauce should be avoided in large amounts by people taking ACE inhibitors.

Interaction With Disease:

  • Bone Marrow Suppression - ACE inhibitors can cause bone marrow depression in patients with renal impairment and should be administered cautiously in patients with preexisting blood dyscrasias.

  • Congestive Heart Failure - ACE inhibitors can cause oliguria and excessive hypotension. Therapy with ACE inhibitors should be monitored closely until the blood pressure and renal function are stabilized.

  • Hyperkalemia - Therapy with ACE inhibitors should be monitored in patients with predisposed hyperkalemia for their serum potassium levels.

What Are the Drug Warnings and Precautions for ACE Inhibitors?

  • Pregnant Women - ACE inhibitors should not be taken during pregnancy as they can increase the risk of adverse events for pregnant women. It can affect the embryo and fetus's development and, therefore, should be avoided.

  • Breastfeeding Women - Angiotensin II receptor antagonists should not be used by breastfeeding women in the first week after delivery as the medicine can pass through breast milk.

  • Children - ACE inhibitors should be given with caution in children as they are at higher risk of severe side effects, such as severe dry cough and allergic reactions.

  • History of Angioedema - ACE inhibitors are contraindicated in patients with past reactions to an ACE inhibitor. It can cause symptoms such as swelling of the face, tongue, and throat, and trouble breathing and swallowing.

  • Severe Kidney Disease - Angiotensin-converting enzyme inhibitors should be administered with caution in patients with severe kidney disease or renal artery stenosis.

  • Geriatrics - ACE inhibitors should be given with caution in the elderly, and the doses should be adjusted accordingly.

  • Liver Disease - Therapy with ACE inhibitors should be administered cautiously in patients with liver issues.

  • Diabetic Nephropathy - Taking ACE inhibitors can exacerbate proteinuria and progress to kidney failure in patients with diabetic nephropathy.

  • Alcohol - Drinking alcohol can increase the blood pressure-lowering effect of Lisinopril and can make one feel dizzy or lightheaded.


ACE inhibitors are important agents to treat and prevent various heart problems and should not be discontinued unless instructed by your doctor. It is, however, important to maintain a healthy lifestyle to control and manage your heart health.

Frequently Asked Questions


What Is the Best ACE Inhibitor for Hypertension?

The most effective ACE inhibitors for hypertension are:
- Trandolapril.
- Enalapril.
- Ramipril.


What Is the Preferred Blood Pressure Medication?

Angiotensin-converting enzyme (ACE) inhibitors lower blood pressure by relaxing blood vessels. Examples include 
- Enalapril. 
- Lisinopril. 
- Perindopril.
- Ramipril.


Is Telmisartan an ACE Inhibitor?

Telmisartan is recommended for the prevention of cardiovascular events in high-risk individuals, with efficacy comparable to the angiotensin-converting enzyme (ACE) inhibitor Ramipril.


What Medications Are It Incompatible With Ace Inhibitors?

Nonsteroidal anti-inflammatory medicines (NSAIDs) such as Ibuprofen and Naproxen sodium reduce the efficiency of angiotensin-converting enzyme inhibitors.


Is It True That Atorvastatin Is an ACE Inhibitor?

Yes, Atorvastatin is a selective, competitive inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, the rate-limiting enzyme that transforms mevalonate into sterol precursors like cholesterol.


Which Is More Effective, an Ace Inhibitor or a Calcium Channel Blocker?

Studies on high-risk individuals indicate that angiotensin-converting enzyme inhibitors offer better protection against cardiovascular events and renal disease than calcium channel blockers and other medications.


For Whom Should ACE Inhibitors Not Be Used?

- Women who are pregnant.
- People suffering from acute renal failure.
- Angiotensin-converting enzyme inhibitors should not be taken by anyone who has ever had a severe allergic reaction that caused their tongue and lips to swell, even if it was caused by a bee sting.


What Are the Common ACE Inhibitors?

The common angiotensin-converting enzyme inhibitors are:
- Captopril.
- Benazepril.
- Enalapril. 
- Fosinopril.
- Moexipril.
- Perindopril.
- Quinapril.


What Is the Optimum Time to Take ACE Inhibitor?

Angiotensin-converting enzyme (ACE) inhibitors function best when taken before night because they lower the action of a hormone that is most active during sleep.


What Are the Most Common Indications for ACE Inhibitors?

The most common indications for angiotensin-converting enzyme inhibitors are:
- Coronary artery disease.
- Heart failure.
- Diabetes.
- Certain chronic renal disorders.
- Heart attacks.
- A skin and connective tissue stiffening disorder (scleroderma)
- Migraines.
- High blood pressure.


What Is the Complete Meaning of ACE?

ACE stands for angiotensin-converting enzyme.


Which of the Following Was the First ACE Inhibitor?

Captopril was the first angiotensin-converting enzyme inhibitor licensed for clinical use (in 1981) and established itself as a potent new therapeutic agent in the treatment of hypertension and heart failure.


What Is the Role of ACE?

Drugs called angiotensin-converting enzyme inhibitors aid in blood pressure reduction by assisting in artery and vein relaxation. Angiotensin-converting enzyme inhibitors stop a bodily enzyme from generating angiotensin II, a chemical that constricts blood vessels.
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Dr. Muhammad Zohaib Siddiq
Dr. Muhammad Zohaib Siddiq



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