Diuretics, also called water pills, are a common treatment for high blood pressure. Find out how they work and when you might need them.By Mayo Clinic Staff
Diuretics, sometimes called water pills, help rid your body of salt (sodium) and water. Most of these medicines help your kidneys release more sodium into your urine. The sodium helps remove water from your blood, decreasing the amount of fluid flowing through your veins and arteries. This reduces blood pressure.
Examples of diuretics
There are three types of diuretics:
- Potassium sparing
Each type of diuretic affects a different part of your kidneys. Some pills combine more than one type of diuretic or combine a diuretic with another blood pressure medication.
Which diuretic is best for you depends on your health and the condition being treated.
Examples of thiazide diuretics taken by mouth include:
Examples of loop diuretics include:
- Bumetanide (Bumex)
- Ethacrynic acid (Edecrin)
- Furosemide (Lasix)
- Torsemide (Soaanz)
Examples of potassium-sparing diuretics include:
- Amiloride (Midamor)
- Eplerenone (Inspra)
- Spironolactone (Aldactone, Carospir)
- Triamterene (Dyrenium)
When diuretics are used
Thiazide diuretics are recommended as one of the first drug treatments for high blood pressure.
If diuretics aren't enough to lower your blood pressure, your doctor might add other blood pressure medications to your treatment plan.
Diuretics are also used to prevent, treat or improve symptoms in people who have:
- Heart failure
- Liver failure
- Tissue swelling (edema)
- Certain kidney disorders, such as kidney stones
Diuretics are generally safe. Side effects include increased urination and sodium loss.
Diuretics can also affect blood potassium levels. If you take a thiazide diuretic, your potassium level can drop too low (hypokalemia), which can cause life-threatening problems with your heartbeat. If you're on a potassium-sparing diuretic, you can have too much potassium in your blood.
Other possible side effects of diuretics include:
- Muscle cramps
- Joint disorders (gout)
Aug. 13, 2021
Get the latest health advice from Mayo Clinic delivered
to your inbox.
Sign up for free, and stay up-to-date on research
advancements, health tips and current health topics,
like COVID-19, plus expert advice on managing your health.
ErrorEmail field is required
ErrorInclude a valid email address
To provide you with the most relevant and helpful information and to understand which
is beneficial, we may combine your e-mail and website usage information with other
information we have about you. If you are a Mayo Clinic Patient,
this could include Protected Health Information (PHI). If we combine this information
with your PHI, we will treat all of that information as PHI,
and will only use or disclose that information as set forth in our notice of privacy
practices. You may opt-out of e-mail communications
at any time by clicking on the Unsubscribe link in the e-mail.
Thank you for Subscribing
Our Housecall e-newsletter will keep you up-to-date
on the latest health information.
We’re sorry! Our system isn’t working. Please try again.
Something went wrong on our side, please try again.
See more In-depth
- Types of blood pressure medications. American Heart Association. https://www.heart.org/en/health-topics/high-blood-pressure/changes-you-can-make-to-manage-high-blood-pressure/types-of-blood-pressure-medications. Accessed July 12, 2021.
- Mann JFE. Choice of drug therapy in primary (essential) hypertension. https://www.uptodate.com/contents/search. Accessed June 25, 2019.
- Cifu AS, et al. Prevention, detection, evaluation and management of high blood pressure in adults. JAMA. 2017;18:2132.
- Brater DC, et al. Mechanism of action of diuretics. https://www.uptodate.com/contents/search. Accessed June 25, 2019.
- Drug record: Diuretics. National Institutes of Health. https://livertox.nlm.nih.gov/Diuretics.htm. Accessed June 25, 2019.
- Reboussin DM, et al. Systematic review for the 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults: A report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Circulation. 2018;138:e595.
- Aronson JK. Diuretics. In: Meyler's Side Effects of Drugs. 16th ed. Amsterdam, Netherlands: Elsevier; 2016. https://www.clinicalkey.com. Accessed July 12, 2021.
- Whelton PK, et al. 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults: A report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Hypertension. 2018;71:e13.