Angiotensin II receptor blockers (ARBs) decrease the effects of angiotensin. This protein causes blood vessels to become too narrow, leading to high blood pressure. ARBs also treat heart failure and kidney disease and lower the risk of heart attacks and strokes. The medicine relaxes blood vessels, so blood flows more freely.
Angiotensin II receptor blockers are medications that treat high blood pressure and heart failure. They are also called angiotensin II receptor blockers or ARBs.
Angiotensin II is a protein. Your liver produces angiotensin, one type of this protein. Enzymes made by your kidneys break down this protein into angiotensin I. Your blood carries angiotensin I through the kidneys and lungs. In the lungs, enzymes convert the protein into angiotensin II.
Everyone makes angiotensin II. It plays an important role in body functions. But some people produce too much of the protein due to heart disease, genetics or other issues.
An excess of angiotensin II can affect the:
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Healthcare providers prescribe ARBs for:
When your body has too much angiotensin, you start to retain fluids. Excess fluid retention causes your blood pressure to go up. And high blood pressure causes the blood vessels to contract or become narrow.
For this constriction to happen, angiotensin II needs another protein (called a receptor) to bind to. ARBs block these receptor proteins so the angiotensin can’t bind and constrict the blood vessel. This allows the blood vessels to relax and stay open. Blood then flows freely and without excessive force.
Medications that end in “-sartan” are ARBs. They include:
ARBs are oral medications. You take the medicine once or twice a day by mouth, depending on which ARB.
High blood pressure often returns when you stop taking a medication. You may need ARBs or another blood pressure medicine for life.
Healthcare providers often prescribe ARBs instead of angiotensin-converting enzyme (ACE) inhibitors. ARBs cause fewer side effects. Both types of drugs reduce the effects of angiotensin.
The main side effect of ARBs is dizziness. In rare instances, ARBs affect blood flow to the kidneys. This problem is more likely to occur if you already have renal artery disease. You’ll have occasional blood tests to check your kidney function.
ACE inhibitors lower angiotensin production. This medicine causes more side effects like:
No. Medicines that lower angiotensin levels, such as ARBs and ACE inhibitors, can cause serious complications during pregnancy. The medications increase the risk of:
If you have high blood pressure before pregnancy, or you develop it during pregnancy (preeclampsia), your healthcare provider will prescribe a different medicine that’s safe for you and your unborn baby.
When you’re taking blood pressure medicine, you should always check with your healthcare provider before taking over-the-counter medicines or supplements. Some medicines for allergies, coughs and colds, as well as nonsteroidal anti-inflammatory drugs (NSAIDs), can increase blood pressure. This counteracts the effects of the ARBs.
ARBs may raise potassium levels. You shouldn’t take potassium supplements or potassium-sparing diuretics with them. Potassium-sparing diuretics such as eplerenone (Inspra™) increase urination but prevent your body from eliminating excess potassium. Too much potassium can lead to hyperkalemia (high blood potassium). High potassium can cause an irregular heartbeat and other heart problems.
If you’re taking an ARB and following a sodium-controlled diet, you should avoid salt substitutes that contain potassium chloride.
A note from Cleveland Clinic
Angiotensin II receptor blockers or ARBs are an effective treatment for high blood pressure, heart failure, kidney disease and other conditions. The medications prevent angiotensin II proteins from binding to receptors in the blood which causes blood vessels to narrow. As a result, blood vessels relax, allowing blood to move freely through the body. ARBs cause few problems, making them a good option for people who can’t take ACE inhibitors due to medication side effects.
Last reviewed by a Cleveland Clinic medical professional on 06/17/2022.
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