Medication

Mykrox

Generic name:

Pharmacist-reviewed drug information from the RxWiki encyclopedia.

Overview

Metolazone is a prescription medication used to treat high blood pressure and fluid retention caused by congestive heart failure or kidney disease. This medication belongs to a group of drugs called diuretics ("water pills"), which help the body get rid of excess fluid  by increasing the amount of salt and water the kidneys remove from the blood.

This medication comes in tablet form and is usually taken once daily. Metolazone can be taken with or without food.

Common side effects of metolazone include headache, stomach pain, and dry mouth. Metolazone may cause drowsiness. Do not drive or operate heavy machinery until you know how it affects you.

What is it used for?

Metolazone is a prescription medication used to treat high blood pressure and fluid retention caused by congestive heart failure or kidney disease.

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

How to take it

Take metolazone exactly as prescribed by your doctor. Follow the directions on your prescription label carefully.

The metolazone dose your doctor recommends will be based on:

  • the condition being treated
  • other medical conditions you have
  • other medications you are taking
  • how you respond to this medication

To treat fluid retention caused by congestive heart failure the recommended dose range is metolazone 5 to 20 mg once daily.

To treat fluid retention caused by kidney disease the recommended dose range is metolazone 5 to 20 mg once daily.

For the treatment of mild to moderate high blood pressure the recommended dose range is metolazone 2½ to 5 mg once daily.

Warnings

Metolazone can cause serious side effects including:

  • electrolyte imbalance. This medication may affect electrolytes including sodium and potassium. Your doctor will check these levels using a blood test. Warning signs of electrolyte imbalance include:
    • dry mouth
    • thirst
    • weakness
    • lack of energy
    • drowsiness
    • restlessness
    • muscle pains or cramps
    • muscle fatigue
    • low blood pressure
    • decreased urination
    • fast heart rate
    • nausea and vomiting
  • worsening of kidney disease
  • worsening of gout
  • sulfa allergy
  • high blood glucose "sugar" concentrations in people with diabetes
  • systemic lupus erythematosus (SLE or lupus) or worsening of lupus

This medication may cause drowsiness or dizziness. Do not drive or operate heavy machinery until you know how it affects you.

Do not take metolazone if you:

  • are allergic to metolazone or any other ingredient of metolazone
  • are not able to produce urine
  • have severe liver disease

Side effects

Serious side effects may occur. See "Drug Precautions" section.

Common side effects include:

  • muscle weakness
  • dizziness
  • cramps
  • thirst
  • stomach pain
  • stomach bloating
  • upset stomach
  • nausea or vomiting
  • diarrhea or constipation
  • headache
  • hair loss
  • dry mouth
  • dizziness
  • drowsiness
  • fatigue
  • insomnia
  • tingling
  • impotence
  • blurred vision

This is not a complete list of metolazone side effects. Ask your doctor or pharmacist for more information.

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

Drug interactions

Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:

  • other medications for high blood pressure
  • "loop diuretics" such as furosemide (Lasix) or torsemide (Demadex) and others
  • nonsteroidal anti-inflammatory medications such as ibuprofen (Motrin, Nuprin) or naproxen (Aleve) and salicylates
  • corticosteroids such as prednisone, hydrocortisone (Cortef), and dexamethasone (Decadron, Dexone, Hexadrol)
  • lithium (Eskalith, Lithobid)
  • medications for diabetes
  • probenecid (Benemid)
  • alcohol
  • narcotics
  • barbiturates such as amobarbital (Amytal), butalbital (Fioricet, Fiorinal), phenobarbital (Luminal) and others
  • digoxin
  • warfarin (Coumadin, Jantoven)

This is not a complete list of metolazone drug interactions. Ask your doctor or pharmacist for more information.

 

Pregnancy

Tell your doctor if you are pregnant or plan to become pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.

Metolazone falls into category B. There are no good studies that have been done in humans with metolazone. But in animal studies, pregnant animals were given this medication, and the babies did not show any medical issues related to this medication.

Breastfeeding

Tell your doctor if you are breastfeeding or plan to breastfeed.

Metolazone has been detected in human breast milk. Because of the possibility for adverse reactions in nursing infants from metolazone, a choice should be made whether to stop nursing or to stop use of metolazone. The importance of the drug to the mother should be considered.

Quick facts

Because metolazone increases urination, it is best taken in the morning to avoid having to get up in the night to urinate.

Metolazone may cause drowsiness. Do not drive or operate heavy machinery until you know how it affects you.

Metolazone can cause the following:

  • worsening of gout
  • high blood glucose "sugar" in people with diabetes

Do not take metolazone if you:

  • are allergic to metolazone or any other ingredient of metolazone
  • are not able to produce urine
  • are allergic to sulfa

All information on this site is provided “as-is” for informational purposes only and is not a substitute for medical advice or treatment. You should consult with a medical professional if you have any questions about your health.