Angiotensin converting enzyme, or "ACE" inhibitors, are a type of medication that doctors prescribe to treat high blood pressure, or hypertension, and other cardiovascular conditions.
This article outlines the different ACE inhibitors that are available. We also discuss the effectiveness of ACE inhibitors, along with their potential side effects and risks.
ACE inhibitors prevent the body from making the hormone Angiotensin II. Ordinarily, this hormone narrows the blood vessels, which causes an increase in blood pressure and forces the heart to work harder.
By inhibiting the production of Angiotensin II, ACE inhibitors keep the blood vessels open. This reduces blood pressure and lowers the risk of complications associated with hypertension.
Most people take ACE inhibitors orally, but some may administer the drug intravenously.
The U.S. Food and Drug Administration (FDA) list the following types of ACE inhibitor:
- benazepril (Lotensin)
- enalapril (Vasotec)
- lisinopril (Zestril and Prinivil)
- quinapril (Accupril)
- ramipril (Altace)
Doctors mainly prescribe ACE inhibitors to treat the following conditions:
- cardiovascular conditions (e.g., high blood pressure, and coronary artery disease)
- heart problems (e.g., heart disease)
- kidney problems (e.g., primary nephrotic syndrome)
Doctors consider some of these uses as off-label. Off-label means that the FDA have approved a drug for one condition, but doctors prescribe it to treat something different.
Most people who take ACE inhibitors do not experience side effects. When side effects do occur, they are usually minor.
A 2019 review of ACE inhibitors describes some of the more common side effects of ACE inhibitors. The table below outlines these side effects, along with how many people experience them.
|Side effect||Percentage of people affected|
|Low blood pressure, or "hypotension"||7–11%|
|Elevated levels of urea, nitrogen, and creatine in the blood (a possible sign of kidney problems)||2–11%|
|High potassium levels, or "hyperkalemia"||2–6%|
A separate 2019 review notes that around 1–10% of people who take ACE inhibitors may develop a dry cough. If a person cannot tolerate this cough, they should seek their doctor's advice on whether to stop taking the medication.
Some people may develop more severe side effects when taking ACE inhibitors. Examples include kidney problems and allergies to the ACE inhibitor. Another severe side effect that can occur is angioedema, which is swelling, typically of the tongue and throat.
People who take ACE inhibitors should contact their doctor if they experience any side effects while on the medication. Anyone who has a swelling of the tongue or throat should call 911.
These drugs can also help people who have high blood pressure due to kidney disease.
When treating high blood pressure, a doctor will often combine the ACE inhibitor with another antihypertensive medication to increase the effects of the drug.
Doctors have found that calcium channel blockers (CCBs) and thiazide diuretics can work well with ACE inhibitors to lower blood pressure.
ACE inhibitors usually do not cause problems when a person takes them as directed.
However, pregnant women should not take ACE inhibitors due to a risk of harm to the fetus. These risks include:
- low amniotic fluid levels
- kidney problems
- abnormal skull development
People who have an allergy to ACE inhibitors should not take the medication.
People with the kidney condition bilateral renal artery stenosis (BRAS) should also avoid these drugs. BRAS is a narrowing of the blood vessels within the kidneys. ACE inhibitors can cause worsening kidney function in people with this condition.
People who are concerned about the potential risks of ACE inhibitors should talk to their doctor.
Beta-blockers and CCBs are two other medications that doctors commonly prescribe to treat heart problems and high blood pressure. Both drugs work differently to ACE inhibitors.
CCBs prevent calcium from interacting with the body's calcium receptors.
Ordinarily, calcium plays a role in contracting the muscles within the heart and blood vessel walls. CCBs block the movement of calcium into the blood vessel walls, causing these walls to relax. This reduces blood pressure and allows the heart to receive more oxygenated blood. By blocking calcium movement into the heart muscles, the heart contracts more slowly. This puts less stress on the heart.
The type of medication a person receives depends on several factors, including their:
- overall health
- medical history
ACE inhibitors are one of the more common medications used to lower blood pressure and treat cardiovascular health issues.
Most people who take ACE inhibitors do not experience side effects. When side effects do occur, they are generally mild.
However, ACE inhibitors are not suitable for everyone. Pregnant women, in particular, should not take these medications.
Doctors often prescribe ACE inhibitors alongside other antihypertensive medications. Combined drug treatments can be particularly useful in controlling high blood pressure.