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Drugs & Medications

metolazone

COMMON BRAND NAME(S): Zaroxolyn

GENERIC NAME(S): METOLAZONE

Uses

Metolazone is a "water pill" (diuretic) that increases the amount of urine you make, which causes your body to get rid of excess water. This drug is used to treat high blood pressure. Lowering high blood pressure helps prevent strokes, heart attacks, and kidney problems.

This medication also reduces swelling/fluid retention (edema) which can result from conditions such as congestive heart failure or kidney disease. This can help to improve symptoms such as trouble breathing.

How to use metolazone

Take this medication by mouth with or without food, usually once daily, or as directed by your doctor. The dosage is based on your medical condition and response to therapy.

If you take this drug too close to bedtime, you may need to wake up to urinate. Therefore, it is best to take this medication at least 4 hours before your bedtime.

Use this medication regularly in order to get the most benefit from it. Remember to use it at the same time each day as directed. It is important to continue taking this medication even if you feel well. Most people with high blood pressure do not feel sick. Do not stop taking this medication without consulting your doctor. It may take up to 3-6 weeks to see a lowering of your blood pressure.

Cholestyramine and colestipol can decrease the absorption of metolazone. If you are taking either of these drugs, separate metolazone from cholestyramine by at least 4 hours and from colestipol by at least 2 hours.

If your condition persists or worsens, contact your doctor or pharmacist.

Side Effects

Dizziness, lightheadedness, headache, blurred vision, loss of appetite, stomach upset, diarrhea, or constipation may occur as your body adjusts to the medication. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

This medication may lead to excessive loss of body water and minerals (including potassium). Tell your doctor immediately if you have any of these unlikely but serious symptoms of dehydration or mineral loss: muscle cramps or weakness, confusion, severe dizziness, unusual dry mouth or thirst, nausea or vomiting, fast/irregular heartbeat, unusual decrease in the amount of urine, fainting, seizures.

Tell your doctor immediately if any of these unlikely but serious side effects occur: numbness/tingling of the arms/legs, decreased sexual ability.

Tell your doctor immediately if any of these highly unlikely but very serious side effects occur: persistent sore throat or fever, easy bleeding or bruising, stomach/abdominal pain, persistent nausea/vomiting, yellowing of eyes/skin.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Precautions

Before taking metolazone, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: severe kidney disease (inability to make urine or anuria).

Before using this medication, tell your doctor or pharmacist your medical history, especially of: kidney disease, liver disease, untreated mineral imbalance (e.g., sodium, potassium), gout, lupus.

If you have diabetes, metolazone may affect your blood sugar levels. Check your blood sugar levels regularly as directed and share the results with your doctor. Tell your doctor immediately if you have symptoms of high blood sugar such as increased thirst/urination. Your doctor may need to adjust your anti-diabetic medication or diet.

This drug may reduce the potassium levels in your blood. Ask your doctor about adding potassium to your diet. A potassium supplement may be prescribed by your doctor.

This medication may make you more sensitive to the sun. Avoid prolonged sun exposure, tanning booths or sunlamps. Use a sunscreen and wear protective clothing when outdoors.

Before having surgery, tell your doctor or dentist that you are taking this medication.

This drug may make you dizzy or cause blurred vision. Do not drive, use machinery, or do any activity that requires alertness or clear vision until you are sure you can perform such activities safely. Limit alcoholic beverages.

To minimize dizziness and lightheadedness, get up slowly when rising from a seated or lying position.

Caution is advised when using this drug in the elderly because they may be more sensitive to its effects, especially dizziness.

Metolazone should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor.

This drug passes into breast milk. Consult your doctor before breast-feeding.

Interactions

Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.

See also the How to Use section.

This drug should not be used with the following medications because very serious interactions may occur: cisapride.

If you are currently using any of these medications, tell your doctor or pharmacist before starting metolazone.

Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: cholestyramine, colestipol, diazoxide, digoxin, dofetilide, lithium.

Check the labels on all your medicines (such as cough-and-cold products, diet aids, or NSAIDs such as ibuprofen, naproxen) because they may contain ingredients that could increase your blood pressure or worsen swelling (edema). Ask your pharmacist for more details.

This product can affect the results of certain lab tests (e.g., parathyroid function tests). Make sure laboratory personnel and your doctors know you use this drug.

This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.

Overdose

If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include fainting, severe weakness, a severe decrease in amount of urine, or slow or shallow breathing.

Notes

Do not share this medication with others. Lifestyle changes such as stress reduction programs, exercise, and dietary changes may increase the effectiveness of this medicine. Talk to your doctor or pharmacist about lifestyle changes that might benefit you.

Laboratory and/or medical tests (e.g., blood mineral levels such as potassium, kidney and liver function tests) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.

Have your blood pressure checked regularly while taking this medication. Discuss with your doctor how to monitor your own blood pressure.

Missed Dose

If you miss a dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

Storage

Store at room temperature (77 degrees F or 25 degrees C) away from light and moisture. Brief storage between 59-86 degrees F (15-30 degrees C) is permitted. Do not store in the bathroom. Keep all medicines away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.

Information last revised July 2014. Copyright(c) 2014 First Databank, Inc.

Images

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ZAROXOLYN 2.5 MG TABLET
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This medicine is a pink, round tablet imprinted with "ZAROXOLYN" and "2 1/2".
METOLAZONE 2.5 MG TABLET
METOLAZONE 2.5 MG TABLET

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pink
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This medicine is a pink, oval tablet imprinted with "E 50".
ZAROXOLYN 5 MG TABLET
ZAROXOLYN 5 MG TABLET

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This medicine is a blue, round tablet imprinted with "ZAROXOLYN" and "5".
METOLAZONE 5 MG TABLET
METOLAZONE 5 MG TABLET

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This medicine is a blue, oval tablet imprinted with "E 55".
METOLAZONE 10 MG TABLET
METOLAZONE 10 MG TABLET

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E 56
This medicine is a yellow, oval tablet imprinted with "E 56".

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Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, expect as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.

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