All About Blood Pressure Medicine

If you have high blood pressure (hypertension), your healthcare provider may prescribe medicine to lower it. There are several kinds of medicines. You may need to take more than one medicine.


Diuretics are often the first medicine your doctor will try to treat your high blood pressure. Diuretics help lower blood pressure by removing excess fluid and salt in the body through the urine. Examples of common diuretics are:

  • Hydrochlorothiazide

  • Furosemide

  • Chlorothiazide

  • Chlorthalidone

  • Spironolactone

One common side effect of this medicine is more urination. Some diuretics also cause you to lose potassium. You may need to take a potassium supplement. This depends on the type of diuretic that you take. Make sure you talk with your healthcare team to know what type of diuretic you take. Ask if you need monitoring of your electrolyte levels and kidney function while taking these types of medicines.

Beta blockers

These block a hormone that increases the heart rate and blood pressure. This helps relax the blood vessels to improve blood flow. Some beta blockers may have more effect on blood pressure and heart function than others. Examples of beta blockers are:

  • Atenolol

  • Carvedilol

  • Metoprolol

  • Nadolol

  • Propranolol

  • Bisoprolol

  • Nebivolol

Make sure you know how to check your heart rate while taking these types of medicines. If you have a history of asthma, beta blockers can make the asthma worse.

ACE inhibitors and ARBs

ACE stands for angiotensin-converting enzyme. ACE inhibitors reduce the production of the enzyme angiotensin. This enzyme makes blood vessels constrict. ACE inhibitors allow blood vessels to expand. This is so that blood can flow more easily and the heart can work more efficiently. Examples of ACE inhibitors are:

  • Benazepril

  • Captopril

  • Enalapril

  • Lisinopril

  • Fosinopril

  • Quinapril

ARBs are angiotensin II receptor blockers. ARBs block the effects of angiotensin. They prevent it from affecting the heart and blood vessels. You may need this medicine if you can't tolerate ACE inhibitors. Examples of ARBs are:

  • Candesartan

  • Losartan

  • Telmisartan

  • Valsartan

  • Irbesartan

Pregnant women should not take ACE inhibitors or ARBs. These medicines can cause a risk of birth defects. If you have high blood pressure and plan to become pregnant or are pregnant, contact your healthcare provider right away.

You should have regular blood tests to make sure these medicines don't affect your kidney function or electrolyte levels. Talk with your healthcare team about how often you should have these blood tests.

Calcium channel blockers

These cause blood vessels to widen (dilate) by reducing the amount of calcium in their cells. Some also slow the heart rate. Some calcium channel blockers are: 

  • Amlodipine

  • Felodipine

  • Verapamil

  • Nifedipine

  • Diltiazem

Alpha blockers

Alpha blockers block a hormone that makes the blood vessels constrict. This helps relax the blood vessels and improve blood flow. Examples of alpha blockers are:  

  • Doxazosin

  • Prazosin

  • Terazosin

Central agonists

This class of medicine stimulates a receptor in the brain that lowers blood pressure and heart rate. An example of this medicine is clonidine.


Vasodilators lower blood pressure by relaxing the blood vessels and improve blood flow. Examples of these medicines are hydralazine and minoxidil.

Guidelines for taking medicines

Blood pressure medicine may cause side effects such as:

  • Headaches

  • Nausea

  • Weakness

  • Insomnia

  • Lightheadedness

  • Swelling

  • Sexual problems

Ask your healthcare provider about changing your prescription if you have side effects.

To benefit from your medicine, follow these guidelines:

  • Take all your medicine as prescribed. Ask if you should take it with food or on an empty stomach.

  • Take your pills at the same time each day. Put a check mark on your calendar after you've taken them.

  • Use a daily or weekly pillbox that you can fill ahead of time. Then you will know if you have taken your medicine each day.

  • Never skip a day or decide not to take your pills because you have side effects or don't feel your blood pressure is high. Remember: High blood pressure often has no symptoms. Contact your healthcare provider about side effects and possible solutions.

  • If you miss a dose or doses, contact your healthcare provider and ask what to do.

  • Before buying any over-the-counter (OTC) medicine, ask the pharmacist or your healthcare provider if it interacts with your blood pressure medicine. This is very important. Some OTC products can have serious interactions with blood pressure medicines.

  • Refill your prescription before it runs out.

  • Take the right amount of medicine each day. Don't adjust your dosage without your healthcare provider's approval.

  • Don't stop taking your medicine if your blood pressure tests normal. It's normal because your medicine is working.

  • Don't skip appointments to have your blood pressure checked or blood tested.

Online Medical Reviewer: Stacey Wojcik MBA BSN RN
Online Medical Reviewer: Steven Kang MD
Date Last Reviewed: 2/1/2021
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