What is a diuretic?

Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
Diuretics (a.k.a. water pills) help the body get rid of water by preventing your kidneys from holding on to it. As a result, you pee out more water than usual. While a little fluid buildup might not seem like a big deal, it can cause serious health problems depending on where it shows up. Heart failure, for example, can cause fluid to build up in the lungs making it hard for a person to breathe. If this happens too quickly, it can be rapidly fatal.

Diuretics should only be taken when prescribed by a doctor to you for a specific reason. You should never use diuretics for weight loss, and you should never take a friend’s or relative’s medication or supplement for any reason.

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John A. Chabot
Endocrinology Diabetes & Metabolism

A diuretic is any drug that elevates the rate of urination. While there are many different types of diuretics, all increase the rate of excretion of water from the body.

Diuretics are medications often prescribed to cardiovascular patients to lower blood pressure, which will help reduce cumulative damage to the heart and arteries. Sometimes called “water pills,” diuretics cause your body to eliminate salt and water (through urine or perspiration), which in turn lowers blood pressure. High blood pressure exerts extra force on the heart and artery walls, damaging them in the process.
In patients where the heart muscle might not be strong enough to pump blood efficiently, diuretics will help reduce fluid that might back up into the lung causing the symptoms of what is termed congestive heart failure.
Ozgen Dogan
Cardiology (Cardiovascular Disease)
Diuretics discharge extra fluid and salt out of the body with the urine, and this helps to lower blood pressure. Hydrochlorothiazide (HCTZ), furosemide, spironolactone, bumetanide, torsemide, and metolazone are all diuretics. It's best not to take a diuretic before you go to bed otherwise you'll be waking up frequently to go to the bathroom. Other side effects are muscle cramps, weariness and thirst. Some diuretics cause potassium loss. Only take them under a doctor's advice.
Diuretics help rid your body of excess fluid and salt. They are often prescribed for high blood pressure and congestive heart failure.

Examples of diuretics include:
  • amiloride (Midamor)
  • bumetanide (Bumex)
  • chlorothiazide (Diuril)
  • ethacrynic acid (Edecrin)
  • furosemide (Lasix)
  • hydrochlorothiazide (Esidrix, Hydrodiuril, Microzide, Oretic)
  • indapamide (Lozol)
  • metolazone (Mykrox, Zaroxolyn)
  • torsemide (Demadex)
  • triamterene (Dyrenium)

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.