Angiotensin II Receptor Blockers (ARBs)

What are angiotensin receptor blockers?

Angiotensin receptor blockers (ARBs) are medicines that lower blood pressure. Lowering the blood pressure reduces or prevents heart attacks or strokes. It also makes it easier to treat heart failure. Examples of medicines that are ARBs are: candesartan, losartan, and valsartan. Which medicine is best for you depends on your condition and health.

When are ARBs used?

ARBs can be used to control high blood pressure and treat heart failure. Reducing blood pressure helps slow the progress of kidney disease, so ARBs may be taken by people with diabetes or high blood pressure to help prevent kidney failure. ARBs also appear to decrease damage to the heart muscle after a heart attack.

Sometimes ARBs may be prescribed if you cannot tolerate another type of medicine called an ACE inhibitor because of certain side effects of the ACE inhibitor. ARBs may be used alone or with other medicines.

How do ARBs work?

ARBs block the action of a substance in your body called angiotensin II. This substance normally causes blood vessels to constrict (squeeze). Too much of this substance can make your blood pressure too high (a condition called hypertension) and increase the workload of the heart and other organs. ARBs can stop angiotensin II from having this effect. The medicine makes the blood vessels relax and open up. This makes it easier for blood to flow through the blood vessels, which lowers blood pressure. ARBs also increase the release of water and sodium (salt) into the urine, which also lowers blood pressure.

What will be checked while I am taking ARBs?

Your healthcare provider will check your blood pressure regularly. You may also have blood tests to check your kidney function and your blood potassium level, especially if you also take diuretics or potassium supplements. If you have heart failure, you need to weigh yourself regularly.

Although ARBs are well tolerated by most people, some people should not take ARBs for a variety of reasons. These reasons may include:

• severe kidney or liver disease
• a history of a severe reaction to this medicine, such as angioedema, which is swelling and redness of the head, mouth, lips, tongue, or neck that can interfere with breathing
• pregnancy or plans to become pregnant because ACE inhibitors may cause birth defects.

When should I call my healthcare provider?

If you have any of the following side effects from this medicine, report them to your provider right away:

• chest pain
• severe dizziness or fainting (this may be a sign your blood pressure is too low)
• skin rashes
• muscle weakness
• swelling of the tissues in your face, eyes, lips, tongue, or throat, especially if you are having trouble breathing.

Not all of the ARBs have the same side effects. If you develop symptoms while taking this medicine, contact your healthcare provider right away. Fortunately, most people taking the drug have no side effects.