section name header

General Information

Class Name(s):

Pronunciation:

Brand Name(s):

Use

WHY is this medicine prescribed?

Metolazone, is used to reduce the swelling and fluid retention caused by heart failure or kidney disease. It also is used alone or with other medications to treat high blood pressure. Metolazone is in a class of medications called diuretics ('water pills'). It causes the kidneys to reduce the amount of water and salt in the body by increasing the amount of urine.

HOW should this medicine be used?

Metolazone comes as a tablet to take by mouth. It is usually taken once a day. Take metolazone at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take metolazone exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Your doctor will probably start you on a low dose of metolazone and gradually increase your dose, depending on your response to this medication.

Metolazone controls high blood pressure but does not cure it. Continue to take metolazone even if you feel well. Do not stop taking metolazone without talking to your doctor.

Are there OTHER USES for this medication?

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Special

What SPECIAL PRECAUTIONS should I follow?

Before taking metolazone,

What SPECIAL DIETARY instructions should I follow?

Follow your doctor's directions. they may include a daily exercise program and a low-sodium or low-salt diet, potassium supplements, and increased amounts of potassium-rich foods (e.g., bananas, prunes, raisins, and orange juice) in your diet.

What should I do IF I FORGET to take a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

Side Effects

What SIDE EFFECTS can this medicine cause?

Metolazone may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:

Metolazone may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

Overdose

What should I do in case of OVERDOSE?

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at http://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include the following:

Storage

What should I know about STORAGE and DISPOSAL of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from light, excess heat and moisture (not in the bathroom).

Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website http://goo.gl/c4Rm4p for more information.

Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location - one that is up and away and out of their sight and reach. http://www.upandaway.org

Miscellaneous

What OTHER INFORMATION should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your body's response to metolazone.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are taking metolazone.

Learn the brand name of your medication. Do not switch brands without talking to your doctor or pharmacist, as different brands of metolazone may work differently in the body.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.

¶ This branded product is no longer on the market. Generic alternatives may be available.

This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.

The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.

AHFS® Patient Medication Information Copyright, 2025. The American Society of Health-System Pharmacists®, 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

Selected Revisions: June 15, 2017.