ACE inhibitors are a class of blood pressure medications that includes 10 FDA-approved drugs, with lisinopril, enalapril, and ramipril among the most widely prescribed. They work by blocking a chemical process that tightens blood vessels, allowing blood to flow more easily and reducing the workload on your heart.
Complete List of ACE Inhibitors
The FDA has approved the following ACE inhibitors, listed here by generic name with common brand names in parentheses:
- Benazepril (Lotensin)
- Captopril (Capoten)
- Enalapril (Vasotec, Epaned)
- Fosinopril (Monopril)
- Lisinopril (Zestril, Prinivil, Qbrelis)
- Moexipril (Univasc)
- Perindopril (Aceon)
- Quinapril (Accupril)
- Ramipril (Altace)
- Trandolapril (Mavik)
All 10 work through the same basic mechanism, but they differ in how quickly they take effect, how long they last, and how your body processes them. Some are taken once daily while others require twice-daily dosing. Most are available as affordable generics.
How ACE Inhibitors Work
Your body has a built-in system for regulating blood pressure. Part of that system involves an enzyme that converts a relatively inactive hormone into a powerful one that narrows blood vessels and tells your kidneys to retain salt and water. ACE inhibitors block that enzyme, which is where the name comes from: angiotensin-converting enzyme inhibitor.
The result is that blood vessels relax and widen, fluid retention decreases, and blood pressure drops. This also reduces the strain on your heart, which is why these drugs are useful beyond just blood pressure control.
What ACE Inhibitors Treat
High blood pressure is the most common reason people take an ACE inhibitor. The 2025 guidelines from the American Heart Association and American College of Cardiology list ACE inhibitors as one of three first-line drug classes for treating high blood pressure in adults, alongside thiazide diuretics and calcium channel blockers.
But these medications pull double duty across several conditions:
- Heart failure: ACE inhibitors help a weakened heart pump more efficiently by reducing the resistance it has to push against.
- After a heart attack: Starting an ACE inhibitor early after a heart attack helps protect the heart muscle during recovery. With lisinopril, for example, treatment typically begins within 24 hours of a heart attack.
- Kidney protection in diabetes: Current guidelines specifically recommend ACE inhibitors for people who have both diabetes and kidney disease, or even early signs of kidney damage, to slow disease progression.
- Chronic kidney disease: Even without diabetes, ACE inhibitors are recommended when kidney disease involves significant protein loss in the urine.
- Stroke and heart attack prevention: For people at high cardiovascular risk, these drugs reduce the chance of a first event.
ACE inhibitors also treat several other kidney conditions, including nephrotic syndrome, excess protein in the urine, and kidney inflammation after a transplant.
Common Side Effects
The most well-known side effect is a persistent dry cough. It’s a nagging, tickling cough that doesn’t produce mucus and doesn’t go away on its own while you’re taking the medication. A large study tracking over 27,000 patients found that about 4% developed a cough severe enough to stop taking the drug. Some of those patients noticed it within the first four weeks, while others didn’t develop it until months or years into treatment. If the cough becomes bothersome, your doctor will typically switch you to a related class of medication called an ARB, which works similarly without triggering the cough.
ACE inhibitors can also raise potassium levels in your blood. Potassium is essential for heart rhythm, but too much of it becomes dangerous. This is why clinical guidelines recommend blood work to check your potassium and kidney function within 30 days of starting the medication. A potassium level at or above 5.5 mEq/L is considered the threshold for concern.
Other possible side effects include dizziness (especially when standing up quickly), headache, fatigue, and a change in taste. A rare but serious reaction called angioedema causes sudden swelling of the face, lips, tongue, or throat. This is a medical emergency and means you should never take an ACE inhibitor again.
Who Should Not Take ACE Inhibitors
ACE inhibitors are strictly off-limits during pregnancy. They can cause serious harm to a developing baby, including skull defects, kidney failure, dangerously low blood pressure, and fetal death. If you’re planning to become pregnant or discover you’re pregnant while taking one, the medication needs to be stopped and replaced with a safer alternative.
Anyone who has previously experienced angioedema from an ACE inhibitor should not take one again. People with certain types of kidney artery narrowing also need to avoid these drugs. And combining an ACE inhibitor with an ARB is specifically warned against in guidelines, as the combination increases the risk of kidney problems and high potassium without added benefit.
Typical Dosing
ACE inhibitors are almost always started at a low dose and gradually increased. Taking lisinopril as the most commonly prescribed example: the starting dose for high blood pressure is usually 10 mg once a day, with a maximum of 40 mg per day. For heart failure, the starting dose drops to 5 mg once daily, with adjustments based on how you respond.
Most ACE inhibitors are taken once daily, making them easy to fit into a routine. Your doctor will check your blood pressure and run blood tests periodically to find the right dose and make sure your kidneys and potassium levels stay in a safe range. It can take a few weeks to see the full blood pressure-lowering effect at any given dose.
Interactions to Be Aware Of
Common pain relievers like ibuprofen and naproxen (NSAIDs) can blunt the blood pressure-lowering effect of ACE inhibitors and increase the risk of kidney problems when used together. Occasional use is generally manageable, but regular NSAID use alongside an ACE inhibitor is something to discuss with your doctor.
Potassium supplements and salt substitutes (which often contain potassium chloride) can push potassium levels dangerously high when combined with an ACE inhibitor. The same goes for potassium-sparing diuretics. If you take any of these, your potassium levels need closer monitoring.