metolazone at a glance
Medicine class
Thiazide-like diuretic, commonly called a water tablet
Main licensed uses
Oedema associated with heart or kidney disease, and mild or moderate hypertension
Food consistency
Take it consistently at the same time in relation to food
Product consistency
Preparations are not automatically interchangeable because absorption can differ
What is metolazone used for?
Licensed uses for the selected product are:
Oedema related to kidney disease, including nephrotic syndrome and impaired renal function
Oedema related to congestive heart failure
Mild or moderate hypertension, alone or with an antihypertensive from another class
How does metolazone work?
Metolazone reduces sodium reabsorption within the kidney tubules. More sodium, chloride and water are passed in urine, reducing excess fluid and helping lower blood pressure.
metolazone preparations and strengths
Tablet
Route: Oral
Strengths: 5 mg
How to take metolazone
Follow the prescription label and do not alter treatment yourself.
Take the tablet consistently at the same time in relation to food.
Swallow it with water.
The scored tablet can be divided into equal halves, but should not be quartered.
Check the product name when collecting supplies and ask a pharmacist about any unexpected change.
metolazone side effects
Common or expected effects
- Nausea, vomiting, constipation or diarrhoea
- Headache, dizziness or fatigue
- Low blood pressure, including dizziness on standing
- Muscle pain or cramps
- Changes in sodium, potassium, magnesium, chloride, uric acid, glucose or kidney blood-test results
Get urgent medical advice
- Severe allergic reaction
- Painful blistering or peeling skin reaction
- Severe dehydration or electrolyte disturbance, which may cause confusion, weakness, cramps, fainting, reduced urine or an irregular heartbeat
- Sudden eye pain or reduced vision
- Seizures, serious blood-cell disorders, pancreatitis, hepatitis or worsening kidney function
metolazone in pregnancy
Metolazone is generally avoided during pregnancy unless a specialist considers it necessary. Diuretics can affect fetal or newborn electrolyte balance, and use in the final trimester is advised against unless absolutely necessary. Contact the prescriber if pregnant, planning pregnancy or if pregnancy is discovered; do not stop without advice.
metolazone while breastfeeding
Metolazone passes into breast milk and may affect the infant; diuretics can also reduce milk production. Discuss breastfeeding plans with the prescriber or specialist.
metolazone interactions
Check prescribed, over-the-counter and herbal products with a pharmacist or prescriber. Important examples include:
Loop diuretics, such as furosemide
The diuretic effect can become much stronger, causing substantial fluid and electrolyte loss.
Lithium
Metolazone can reduce lithium clearance and increase the risk of toxicity.
NSAIDs, such as ibuprofen or naproxen
They may reduce blood-pressure and diuretic effects and increase the risk of kidney impairment.
Digoxin and other cardiac glycosides
Common questions about metolazone
Answers are fully visible for fast scanning and source review.
What is metolazone used for?
It is licensed for fluid retention associated with heart or kidney disease and for mild or moderate high blood pressure.
Can metolazone be taken with furosemide?
They may be prescribed together, but the combination can cause large or prolonged fluid and electrolyte losses and requires close clinical supervision.
Why do I need blood tests?
Tests check kidney function and salts such as sodium and potassium because metolazone can cause dehydration and electrolyte disturbance.
Can metolazone make me dizzy?
Yes. Dizziness may result from low blood pressure, particularly on standing, or from dehydration and electrolyte changes.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.