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.
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)
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
- 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.