Angiotensin II receptor antagonists

Angiotensin II receptor antagonists are prescription blood pressure medicines commonly used to treat hypertension (high blood pressure). They are often referred to as ARBs, which stand for angiotensin II receptor blockers. These medications help relax blood vessels, allowing blood to flow more easily through the body. As a result, they lower blood pressure and reduce stress on the heart, kidneys, and blood vessels.

Angiotensin II receptor antagonists are widely used in healthcare because they are effective and generally well tolerated. They are frequently prescribed as a first-line option for the treatment of hypertension, especially in people who cannot tolerate ACE inhibitors due to side effects like a dry cough.

These medications play an important role in managing long-term cardiovascular disease. They are often part of a broader treatment plan that may include lifestyle changes, such as healthy eating, exercise, and weight management, as well as other antihypertensive medications like diuretics or calcium channel blockers, such as amlodipine.

Angiotensin II receptor antagonists are medications that block the action of angiotensin II, a hormone in the body that raises blood pressure. Angiotensin II causes blood vessels to narrow, increases sodium and water retention, and stimulates the release of aldosterone. Together, these effects raise blood pressure and increase strain on the heart.

ARBs work within the renin-angiotensin system, a key hormone system that regulates blood pressure, fluid balance, and blood vessel tone. The inhibition of angiotensin II at the angiotensin II type 1 receptor prevents blood vessel tightening and helps keep blood vessels relaxed.

Angiotensin II receptor antagonists are commonly prescribed for long-term use and are taken once daily in most cases. They are used by millions of people worldwide to manage hypertension and reduce the risk of serious heart and kidney complications.

Angiotensin II receptor antagonists work by blocking angiotensin II from attaching to angiotensin II type 1 receptors (AT1 receptors) found on blood vessels, kidneys, and other tissues. When angiotensin II binds to these receptors, it causes vasoconstriction, which narrows blood vessels and raises blood pressure.

By preventing this interaction, ARBs promote vasodilation, meaning the blood vessels relax and widen. This lowers resistance in the blood vessels and helps reduce blood pressure. With less resistance, the heart does not need to pump as hard, which lowers the risk of heart failure and myocardial infarction.

ARBs also reduce the release of aldosterone, which helps decrease sodium and water retention. This further supports blood pressure control and reduces fluid buildup. Unlike angiotensin-converting enzyme inhibitors (ACE inhibitors), ARBs do not significantly affect bradykinin levels, which is why they are less likely to cause a dry cough or angioedema.

Overall, the mechanism of action of ARBs leads to improved blood flow, reduced blood pressure, and long-term protection of the heart, kidneys, and blood vessels.

There are several angiotensin II receptor antagonists available. Each of these blood pressure medications works similarly but may differ slightly in duration, dosing, or specific approved uses. Common ARBs include:

• Cozaar (losartan).
• Diovan (valsartan).
• Avapro (irbesartan).
• Atacand (candesartan).
• Micardis (telmisartan).
• Benicar (olmesartan).
• Teveten (eprosartan).
• Edarbi (azilsartan).

Some ARBs are available as combination products with diuretics such as hydrochlorothiazide to improve blood pressure control. Your healthcare provider will select the medication based on your blood pressure goals, kidney function, other medical conditions, and tolerability.

Angiotensin II receptor antagonists are primarily used for the treatment of hypertension. Lowering blood pressure helps reduce the risk of heart attack, stroke, and other cardiovascular disease complications.

These medications are also used to treat congestive heart failure by reducing strain on the heart and improving circulation. In people with kidney disease, especially diabetic nephropathy, ARBs help slow kidney damage and reduce protein loss in the urine.

Angiotensin II receptor antagonists may be prescribed after a myocardial infarction to help protect the heart and prevent future events. They are often used when ACE inhibitors such as lisinopril are not tolerated.

Most people tolerate angiotensin II receptor antagonists well, but side effects can occur. Common side effects may include:

• Dizziness or lightheadedness.
• Fatigue.
• Headache.
• Low blood pressure.
• Diarrhea or stomach upset.

Less common but more serious side effects may include:

• High potassium levels are especially common in people with kidney disease.
• Worsening kidney function.
• Severe drops in blood pressure.
• Rare cases of angioedema.

Compared to ACE inhibitors, ARBs have a lower incidence of dry cough and angioedema, which improves tolerability for many patients. Your healthcare provider may monitor potassium levels and kidney function with blood tests, especially during the early stages of treatment.

These are not all of the possible side effects of angiotensin II receptor antagonists. You should always seek medical advice from your healthcare provider for any questions or concerns about your medical condition or treatment. Read all patient information, medication guides, or drug information sheets that come with this medication. You can also report adverse effects to the Food and Drug Administration at www.fda.gov/medwatch or 1-800-FDA-1088.

Although these medications are generally well-tolerated and safe, there are certain warnings, precautions, and drug interactions you should be aware of.

Warnings

Before starting angiotensin II receptor antagonists, it is crucial to discuss any existing health conditions with your healthcare provider. You should be sure that your healthcare provider is aware of all your medical conditions, including if you have:

• Kidney disease or renal artery stenosis.
• Liver disease or dysfunction.
• Low blood pressure or dehydration.
• High potassium levels.
• Heart failure.
• Diabetes.
• A history of angioedema.

Your healthcare provider may monitor blood pressure, kidney function, and potassium levels, especially when starting therapy or adjusting the dose.

Boxed Warning

• Angiotensin II receptor antagonists should not be used during pregnancy. These medications can cause serious harm or death to an unborn baby. If you become pregnant while taking this medication, stop taking it and contact your healthcare provider immediately.

Contraindications

Angiotensin II receptor antagonists should not be used in people who:

• Are pregnant.
• Have known hypersensitivity to these medications.
• Are taking aliskiren and have diabetes.

Your healthcare provider will determine if ARBs are appropriate for you based on your overall health and risk factors.

Drug interactions

When angiotensin II receptor antagonists are taken with other prescription drugs, over-the-counter medications, vitamins, and supplements, they may change how they work or increase the risk of side effects. Tell your healthcare professional about everything you take, including:

• Potassium supplements or salt substitutes.
• Potassium-sparing diuretics.
• NSAIDs.
• Other blood pressure medicines.
• Supplements that affect potassium levels.

Some interactions may increase the risk of kidney problems, low blood pressure, or high potassium levels.