What is this medication?

Diuretics are also called “water pills.” They are usually taken with other medications.

Diuretics include:

  • chlorthalidone
  • ethacrynic acid (Edecrin)
  • furosemide (Lasix)
  • hydrochlorothiazide
  • indapamide (Lozide)
  • metolazone (Zaroxolyn)

Be aware:

  • Generic names are listed first.
  • Canadian brand names are in brackets.
  • This list doesn’t include every brand name.
  • If your prescription isn’t listed, your pharmacist is the best source for more information.
What do diuretics do?

These drugs treat high blood pressure and heart failure. They do it by helping your kidneys produce more urine.

  • The more you urinate, the more excess salt and water you flush out of your body.
  • Without the extra fluid, it’s easier for your heart to pump.

Key facts about diuretics. They:

  • lower your blood pressure
  • can relieve shortness of breath
  • reduce swelling and bloating
  • make you urinate more often
  • reduce the time you spend in hospital
  • help you to live longer with heart failure.
How do I take a diuretic?

Take your diuretic exactly as prescribed.

  • Take it at least six hours before bedtime to help avoid getting up in the night.
Are there any interactions?

Some medications can stop your heart medicine from working properly. They may even cause other health problems.

Water pills can affect your routine.

  • Your kidneys will make more urine (pee). You will need to use the bathroom more often. To avoid getting up at night, take your medication at least six hours before bedtime.
  • Limit your salt.
  • Do not use salt substitutes without first talking to your healthcare provider or pharmacist.
  • Ask if you should restrict your fluids.
  • Some diuretics can cause you to lose potassium. Ask your pharmacist if you should eat foods rich in potassium or take a potassium supplement. If you are on other medications that retain potassium, you may not need extra potassium.
  • You may be asked to weigh yourself every day or two. Rapid weight gain can be a sign of water retention.

Be aware: Furosemide may cause your skin to be more sensitive to sunlight. Protect yourself from sunburn.

Always tell your healthcare provider or pharmacist about any other medications you are taking. These include:

  • prescriptions
  • non-prescription drugs
  • inhalers
  • creams or ointments
  • over-the-counter or natural health products
  • alternative therapies
  • vitamins, minerals or supplements
  • herbal remedies
  • homeopathic medicines
  • traditional remedies, such as Chinese medicines
  • probiotics
  • amino acids or essential fatty acids.
Are there any side effects?

Most people have no problem with diuretics.

Call your healthcare provider or pharmacist if you experience:

  • dehydration
    • not enough urine
    • dry mouth
    • decreased skin “springiness”
    • muscle cramps
    • weakness
    • fever, sore throat or skin rash.
  • dizziness
    • If you feel dizzy or faint, limit how much alcohol you drink.
  • upset stomach.

If you have side effects, talk to your pharmacist or healthcare provider.

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Lifestyle changes that can also help

There are two ways to control and manage your heart health: medication and lifestyle.

Medication can help you control heart disease and high blood pressure, but it cannot cure it.

A healthy lifestyle can help you keep medication to a minimum.

Visit heartandstroke.ca/get-healthy. Learn how to keep your heart healthy with current information and advice from Heart & Stroke Foundation experts.

Talk to your healthcare provider about the most beneficial lifestyle goals for you.

Related information

Your healthcare provider or pharmacist are your best sources of information. You can also learn more about medications at any of these trusted sites.

Managing your medications

Health Canada - Drugs and Health Products
Provides health and medical information for Canadians to maintain and improve their health.

Learn more about:

Your ministry of health also offers health resources in your province or territory. For example, Ontario’s MedsCheck program provides free pharmacist consultations. And British Columbia’s Senior Healthcare web page provides information about important health programs.


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