Zaroxolyn (Metolazone) belongs to the class of medications called diuretics. It is used to treat blood pressure and to remove excessive water (edema) that occurs in such conditions as Congestive Heart Failure and some forms of Kidney Disease.

It usually takes 3 to 4 days for Zaroxolyn (Metolazone) to start reducing edema, and 3 to 6 weeks to start reducing blood pressure.

Zaroxolyn (Metolazone) may be available under multiple brand names and/or in several different forms. Any specific brand name of Zaroxolyn (Metolazone) may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of Zaroxolyn (Metolazone) may not be used for all of the conditions discussed here.

Your doctor may have suggested Zaroxolyn (Metolazone) for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking Zaroxolyn (Metolazone), speak to your doctor. Do not stop taking Zaroxolyn (Metolazone) without consulting your doctor.

Do not give Zaroxolyn (Metolazone) to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take Zaroxolyn (Metolazone) if their doctor has not prescribed it.

The recommended dose of Zaroxolyn (Metolazone) ranges from 2.5 mg to 20 mg daily depending on the condition being treated and the circumstances of the person taking the medication. For treatment of high blood pressure, the usual dose is 2.5 mg to 5 mg once daily. For treatment of edema, the usual dose ranges from 5 to 20 mg once daily.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

It is important to take this medication exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store Zaroxolyn (Metolazone) at room temperature, protect it from light and moisture, and keep it out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Zaroxolyn (Metolazone). If you are concerned about side effects, discuss the risks and benefits of Zaroxolyn (Metolazone) with your doctor.

The following side effects have been reported by at least 1% of people taking Zaroxolyn (Metolazone). Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• decreased sexual ability
• Diarrhea
• dizziness or lightheadedness when getting up from a lying or sitting position
• fatigue
• increased sensitivity of skin to sunlight
• loss of appetite
• upset stomach

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• flu-like symptoms (e.g., Fever or chills, sore throat, cough, achiness)
• joint pain
• skin rash or Hives
• signs and symptoms of too much potassium loss:
• dryness of mouth
• increased thirst
• irregular heartbeat
• mood or mental changes
• muscle cramps or pain
• nausea or vomiting
• unusual tiredness or weakness
• weak pulse
• signs and symptoms of too much sodium loss:
• confusion
• convulsions
• decreased mental activity
• irritability
• muscle cramps
• unusual tiredness or weakness

• signs of kidney problems (e.g., increased urination at night, decreased urine production, blood in the urine, change of urine colour)
• signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
• symptoms of high blood sugar (e.g., frequent urination, increased thirst, excessive eating, unexplained weight loss, poor wound healing, infections, fruity breath odour)

Stop taking the medication and seek immediate medical attention if any of the following occur:

• chest pain
• signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)
• signs of pancreatitis (e.g., abdominal pain on the upper left side, back pain, nausea, fever, chills, rapid heartbeat, swollen abdomen)
• signs of a severe skin reaction such as blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with fever or discomfort

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Zaroxolyn (Metolazone).

Each pink, slightly biconvex tablet, debossed with its numeric strength on one side and "ZAROXOLYN" on the other, contains Zaroxolyn (Metolazone) 2.5 mg. Nonmedicinal ingredients: microcrystalline cellulose, D&C Red No. 33 Aluminum Lake, and magnesium stearate. Zaroxolyn (Metolazone) does not contain alcohol, gluten, lactose, paraben, sucrose, or tartrazine.

Do not take Zaroxolyn (Metolazone) if you:

• are allergic to Zaroxolyn (Metolazone) or any ingredients of Zaroxolyn (Metolazone)
• are unable to urinate

Do not give Zaroxolyn (Metolazone) to people who are in hepatic coma or pre-coma.

There may be an interaction between Zaroxolyn (Metolazone) and any of the following:

• aclidinium
• alcohol
• Aldesleukin
• Allopurinol
• alpha blockers (e.g., Alfuzosin, Doxazosin, Tamsulosin)
• Amiodarone
• amphetamines (e.g., Dextroamphetamine, Lisdexamfetamine)
• angiotensin converting enzyme inhibitors (ACEIs; Captopril, Ramipril)
• antihistamines (e.g., cetirizine, doxylamine, Diphenhydramine, Hydroxyzine, Loratadine)
• antipsychotics (e.g., Chlorpromazine, Clozapine, Haloperidol, Olanzapine, Quetiapine, Risperidone)
• atropine
• barbiturates (e.g., butalbital, Phenobarbital)
• belladonna
• Benztropine
• beta 2 agonists (bronchodilators; e.g., salbutamol, formoterol, Indacaterol)
• brimonidine
• calcium supplements (e.g., calcium carbonate, calcium citrate)
• Carbamazepine
• Cholestyramine
• Colestipol
• corticosteroids (e.g., beclomethasone, Dexamethasone, fluticasone, Hydrocortisone, Prednisone)
• Cyclobenzaprine
• Cyclophosphamide
• Darifenacin
• diabetes medications (e.g., chlorpropamide, insulin, Glyburide, Metformin, Rosiglitazone)
• Digoxin
• Disopyramide
• other diuretics (water pills; e.g., Furosemide, Hydrochlorothiazide, triamterene)
• dofetilide
• Duloxetine
• Flavoxate
• glycopyrrolate
• ipratropium
• Ivabradine
• ketotifen
• levodopa
• lithium
• medications that lower blood pressure Methadone
• Methylphenidate
• multivitamin/mineral supplements
• narcotic pain relievers (e.g., Codeine, Fentanyl, Morphine, Oxycodone)
• nitrates (e.g., Nitroglycerin, isosorbide dinitrate, isosorbide mononitrate)
• nonsteroidal anti-inflammatory medications (NSAIDs; e.g., Ibuprofen, Naproxen)
• Obinutuzumab
• orphenadrine
• Oxcarbazepine
• Oxybutynin
• phosphodiesterase 5 inhibitors (e.g., Sildenafil, Tadalafil, Vardenafil)
• pentixifylline
• Porfimer
• quinine
• quinidine
• scopolamine
• selective serotonin reuptake inhibitors (SSRIs; e.g., Citalopram, Fluoxetine, Paroxetine, Sertraline)
• sodium phosphates
• Solifenacin
• tiotropium
• Tizanidine
• tolcapone
• Tolterodine
• Topiramate
• Tranylcypromine
• tricyclic antidepressants (e.g., Amitriptyline, Clomipramine, Desipramine, Trimipramine)
• umeclidinium
• Verteporfin
• vitamin D analogues (e.g., alfacalcidol, Calcitriol, cholecalciferol)
• Yohimbine

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Zaroxolyn (Metolazone). Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.