ACE Inhibitors

What is an ACE inhibitor?

Angiotensin-converting enzyme inhibitors (ACE inhibitors or ACE-I, for short) are medicines that can lower your blood pressure and protect your kidneys. Healthcare providers often use this drug class to treat cardiovascular (heart and blood vessel) conditions like high blood pressure.

ACE inhibitors help with:

• Treating high blood pressure (hypertension)
• Treating heart failure (inability of your heart to pump enough blood)
• Treating you after a heart attack (lack of blood flow to your heart muscle)
• Treating you after acute coronary syndrome (blockage slowing or stopping blood flow to your heart) — note that the medicine doesn’t treat the blockage itself
• Preventing heart attack and stroke in people at high risk for either
• Preventing and slowing the progression of kidney failure in people with diabetes

ACE inhibitor medications also treat several kidney diseases in people who don’t have diabetes, including:

• Nephrotic syndrome (having kidney damage or its symptoms)
• Proteinuria (too much protein in your urine)
• Glomerular disease (problems with your kidney’s filtration system)
• Post-transplant glomerulonephritis (kidney inflammation and filtration problems)

How do ACE inhibitors work?

ACE inhibitor medications work just like the name suggests. They keep angiotensin-converting enzyme (ACE) from converting angiotensin (AN-gee-oh-ten-sin) I into angiotensin II.

Angiotensin II raises blood pressure in multiple ways, like tightening your blood vessels and limiting how much salt and water your kidneys remove from your body. ACE also breaks down bradykinin, a protein that relaxes your blood vessels and helps your kidneys remove sodium from your body. Both actions help your blood pressure go down.

Reducing the amount of angiotensin II in your body is an effective way to lower blood pressure. Blocking ACE means there’s less angiotensin II to raise your blood pressure, and there’s more bradykinin to lower your blood pressure. That means better blood pressure readings for you.

Types of ACE inhibitors

Examples of ACE inhibitors include:

• Benazepril (Lotensin®)
• Captopril (Capoten®)
• Enalapril (Epaned® and Vasotec®)
• Enalaprilat (Vasotec®)
• Fosinopril
• Lisinopril (Qbrelis®, Zestril® or Prinivil®)
• Moexipril (Univasc®)
• Perindopril
• Quinapril (Accupril®)
• Ramipril (Altace®)
• Trandolapril (Mavik®)

You take all of these ACE inhibitor drugs by mouth except for enalaprilat. You receive this through an IV in your arm.

What are the advantages of ACE inhibitors?

Healthcare providers often make ACE inhibitors their first choice for treating high blood pressure and other cardiovascular conditions. This is because:

• They work. Extensive scientific research has shown that ACE inhibitors are effective.
• They’re preventive. ACE inhibitors don’t just treat existing conditions. They can also prevent those issues from happening (either for the first time or again).
• They often combine well with other drugs. Companies that make medicines often combine ACE inhibitors with certain other types of blood pressure medications into a single drug.
• They’re safe. Side effects of ACE inhibitors are usually minor. Severe side effects are especially rare. In many cases, you can take ACE inhibitors for the rest of your life.

What are the side effects of ACE inhibitors?

Most side effects of ACE inhibitors are minor, but some are serious and need immediate medical care.

In general, the most common side effects for almost all ACE inhibitors include:

• Dry cough
• Dizziness
• Headache
• Drowsiness
• Angioedema (swelling)
• Fatigue
• Weakness

Less common ACE inhibitor side effects include:

• Decreased ability to taste or a noticeable metallic taste
• Upset stomach or nausea
• Rash

How quickly do ACE inhibitors work?

Some ACE inhibitor medications can start working one hour after you take them. You should take certain ACE inhibitors one hour before eating a meal. This is because having food in your digestive system may lower your body’s ability to absorb the medicine by about 30% to 40%. Your provider can tell you if you should take your medicine before eating.

How can I take care of myself while taking this medication?

If you miss a dose of your ACE inhibitor — unless it’s closer to the time for your next dose than the one you missed — you should take the dose as soon as possible. If it’s been too long, wait and take only the next dose. Don’t take more than your prescribed dose to “catch up” because this can make your blood pressure too low.

You shouldn’t stand up too quickly after you start taking angiotensin-converting enzyme inhibitors. Standing up too quickly can make you feel dizzy or pass out.

Keep taking ACE inhibitors as prescribed. Talk to your healthcare provider before you stop taking these medications. Stopping them suddenly can cause a heart attack, stroke or worsening heart failure. If you’re having bad side effects, your healthcare provider can help you switch to another drug.

At least once a year, your provider will check your kidney function and electrolyte levels. This may involve blood and urine testing. If your levels are abnormal or your kidneys aren’t working well, your provider may adjust your ACE inhibitor dose.

What are the reasons I should not take these medications?

Some general reasons for avoiding angiotensin-converting enzyme inhibitors include:

• Pregnancy or breastfeeding (chestfeeding)
• History of angioedema (swelling reaction)
• Any past reaction to an ACE inhibitor
• Severe kidney disease or narrowing of the arteries that supply blood to your kidneys (renal artery stenosis)

Providers recommend switching medicines before trying to get pregnant.

What should you avoid when taking ACE inhibitors?

ACE inhibitor drugs can interact with many medications. A few possible serious interactions include:

• Nonsteroidal anti-inflammatory drugs (NSAIDs). These over-the-counter pain and inflammation medications can make ACE inhibitors less effective or decrease kidney function.
• Medications that affect your potassium or sodium levels. These can make your levels too low or high, like having too much potassium in your blood (hyperkalemia).
• Angiotensin-receptor blockers. When you take an ARB with an ACE inhibitor, they can sometimes affect your kidney function, lower blood pressure and cause hyperkalemia.
• Medications that affect your kidneys. One example is aliskiren, which inhibits an enzyme called renin. This enzyme helps manage your body’s blood pressure.

Your provider may want you to avoid or limit salt in the foods you eat. You may also want to avoid salt substitutes that contain potassium until you talk to your provider about whether they’re right for you.

While it isn’t dangerous, capsaicin — the chemical compound that makes foods like peppers spicy — can sometimes worsen an ACE inhibitor-related cough.

When should I see my healthcare provider?

You should seek immediate medical attention if you experience any of the following while taking ACE inhibitors:

• Swelling (especially in your face, mouth or throat) that may indicate angioedema
• Any symptom of an allergic reaction, especially hives, itching or trouble swallowing or breathing
• Fainting (passing out) or almost passing out
• Any symptoms of a heart attack or stroke
• Jaundice (yellowing of the whites of your eyes or your skin, which can be a sign of serious liver problems)