Table of ContentsView AllTable of ContentsUsesTypesSide EffectsRisksHow They Work
Table of ContentsView All
View All
Table of Contents
Uses
Types
Side Effects
Risks
How They Work
Diuretics, also known as “water pills,” increase the flow of urine and help your kidneys remove salt from your body.
This article discusses what diuretics treat and how they work. It also covers the types of diuretics, side effects, risks, and complications.
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What Do Diuretics Treat?
Healthcare providers may prescribe diuretics to decrease fluid levels when treating various conditions. These include:
In some cases, diuretics may need to be taken long-term. In others, they can be discontinued once symptoms improve.
Diuretics are sometimes taken alongside other medications to treat conditions like high blood pressure and heart failure.
Types of Diuretics
There are several types of diuretics your healthcare provider may prescribe. Each medication has a different way that it works to remove fluid or salt from the body. Your healthcare provider will consider your specific condition, benefits, and risks when working with you to choose a diuretic.
Some diuretics can be purchased over-the-counter, but their effects are typically milder than a prescription.Many over-the-counter diuretics are herbal remedies, like dandelion root. Herbal supplements aren’t regulated like medications and may cause drug interactions. Always check with a healthcare provider before taking a supplement.
Carbonic Anhydrase Inhibitors
Carbonic anhydraseinhibitors, likeacetazolamide, are mainly used to lower fluid pressure in the eye to treatglaucoma.
Sodium-Glucose Cotransporter 2 (SGLT2) Inhibitors
Sodium-glucose cotransporter 2 (SGLT2) inhibitors decrease the glucose and sodium going back into your blood. With fewer sodium ions reabsorbed in your blood, fluid levels decrease, which makes these drugs act as mild diuretics.
SGLT2 drugs like Invokana (canagliflozin) and Farxiga (dapagliflozin) are often used to treat diabetes because they decrease glucose in your blood.
Loop Diuretics
Loop diuretics affect a part of your kidneys called the loop of Henle. They remove salt and excess water from your body.
Loop diuretics may also cause you to lose too much potassium. If the potassium loss is severe enough,hypokalemia(low potassium levels) can result. In severe cases, hypokalemia can lead to abnormal heart rhythms and even cause it to stop.
Loop diuretics, such as Lasix (furosemide), are used to treathypertension(high blood pressure), fluid in the lungs (pulmonary edema), generalized swelling, andhyperkalemia(dangerously high potassium levels).As an off-label use, they may be prescribed for hypercalcemia or high calcium levels.
Thiazides
Thiazidesprevent the reabsorption of sodium and water in the nephrons, the parts of the kidney responsible for filtering fluids and waste that make up urine. This causes more water to leave the body as urine.
Like loop diuretics, thiazides can also cause the levels of potassium in your body to drop. Your doctor will monitor your potassium levels while you’re taking the medicine.
Thiazides are a first-line treatment (i.e., one of the first recommended treatments) for high blood pressure (hypertension). In fact, a 2019 study found that thiazides are more effective as a first-line treatment of hypertension than ACE inhibitors, another common treatment.
When theglomerularfiltration rate(a measure of kidney function) is very low, thiazides may not work as well. In some cases, thiazides may be combined with loop diuretics to increase their effects.
Thiazides are also used to treat calcium-containing kidney stones anddiabetes insipidus.
Thiazide and loop diuretics should never be taken with nonsteroidal anti-inflammatory drugs (NSAIDs) like Advil (ibuprofen) or Aleve (naproxen). When used with thiazide or loop diuretics, these medications can suppress kidney function, potentially causing acute kidney failure.
Potassium-Sparing Diuretics
Osmotic Diuretics
Osmotic diuretics draw in water through osmosis. Osmosis is the passing of water from a less concentrated solution to a more concentrated solution.
Osmotic diuretics prevent water from being reabsorbed and allow it to exit the body. They work in the kidneys as well as around the brain and eye to draw off water and reduce swelling. This can treat glaucoma as well as increased intracranial pressure.
Osmotic diuretics are also used to prevent acute kidney (renal) failure afterchemotherapyorrhabdomyolysis(muscle breakdown).
Vaptans
What Are Natural Diuretics?Some herbs and supplements may act as natural diuretics. These include dandelion, ginger, juniper, hawthorn, and parsley. Always check with your healthcare provider before taking a supplement to make sure it’s safe for you.
What Are Natural Diuretics?
Some herbs and supplements may act as natural diuretics. These include dandelion, ginger, juniper, hawthorn, and parsley. Always check with your healthcare provider before taking a supplement to make sure it’s safe for you.
Side Effects of Diuretics
Diuretics can cause side effects that include:
Risks and Complications
Thiazide and loop diuretics can decrease potassium levels. Your healthcare provider may advise you to limit salt intake and increase potassium-rich foods if you take these types of diuretics.
In contrast, potassium-sparing diuretics may cause potassium levels to become too high. This can potentially lead to dangerous heart-rhythm conditions or cardiac arrest.
If you take diuretics, ask your healthcare provider if you need to have your potassium levels and kidney function checked periodically.
Diuretics could also contribute to dehydration due to fluid loss if you aren’t drinking enough water.
How Diuretics Work
Diuretics help your kidneys remove salt from your body. This helps your body produce more urine. Flushing out the excess sodium helps reduce blood volume, which can lower blood pressure and help your heart pump more efficiently.
It usually takes about one to two hours for diuretics to start working.
Summary
15 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Kehrenberg MCA, Bachmann HS.Diuretics: a contemporary pharmacological classification?.Naunyn Schmiedebergs Arch Pharmacol. 2022;395(6):619-627. doi:10.1007/s00210-022-02228-0HCA Virginia Physicians.The truth about water pills and weight loss.American Academy of Ophthalmology.Acetazolamide: considerations for systemic administration.Simes BC, MacGregor GG.Sodium-glucose cotransporter-2 (SGLT2) inhibitors: a clinician’s guide.Diabetes Metab Syndr Obes. 2019;12:2125–2136. doi:10.2147/DMSO.S212003Oh SW, Han SY.Loop diuretics in clinical practice.Electrolyte Blood Press. 2015;13(1):17-21. doi:10.5049/EBP.2015.13.1.17UpToDate.Diuretics and calcium balance.Suchard MA, Schuemie MJ, Krumholz HM, et al.Comprehensive comparative effectiveness and safety of first-line antihypertensive drug classes: a systematic, multinational, large-scale analysis.Lancet. 2019;394(10211):1816-1826. doi:10.1016/S0140-6736(19)32317-7Butt AK, Patel J, Shirwany H, Mirza Q, Hoover J, Khouzam RN.Beneficial extracardiac effects of cardiovascular medications.Curr Cardiol Rev. 2022;18(2):e151021197270. doi:10.2174/1573403X17666211015145132National Library of Medicine: MedlinePlus.Amiloride.Abdallah HM.New trends in pharmacological treatment of acute kidney injury.Asian Pac J Trop Biomed. 2021;11(7):285-97. doi:10.4103/2221-1691.317241Wang C, Xiong B, Cai L.Effects of tolvaptan in patients with acute heart failure: A systematic review and meta-analysis.BMC Cardiovasc Disord. 2017;17(1). doi:10.1186/s12872-017-0598-yTexas Heart Institute.Diuretics.Harvard Health Publishing.Tips for taking diuretic medications.Puga A, Lopez-Oliva S, Trives C, Partearroyo T, Varela-Moreiras G.Effects of drugs and excipients on hydration status.Nutrients. 2019;11(3):669. doi:10.3390/nu11030669Brater DC, Ellison DH.Mechanism of action of diuretics. In: Sterns RH, Emmett M, eds.UpToDate. UpToDate, 2024.
15 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Kehrenberg MCA, Bachmann HS.Diuretics: a contemporary pharmacological classification?.Naunyn Schmiedebergs Arch Pharmacol. 2022;395(6):619-627. doi:10.1007/s00210-022-02228-0HCA Virginia Physicians.The truth about water pills and weight loss.American Academy of Ophthalmology.Acetazolamide: considerations for systemic administration.Simes BC, MacGregor GG.Sodium-glucose cotransporter-2 (SGLT2) inhibitors: a clinician’s guide.Diabetes Metab Syndr Obes. 2019;12:2125–2136. doi:10.2147/DMSO.S212003Oh SW, Han SY.Loop diuretics in clinical practice.Electrolyte Blood Press. 2015;13(1):17-21. doi:10.5049/EBP.2015.13.1.17UpToDate.Diuretics and calcium balance.Suchard MA, Schuemie MJ, Krumholz HM, et al.Comprehensive comparative effectiveness and safety of first-line antihypertensive drug classes: a systematic, multinational, large-scale analysis.Lancet. 2019;394(10211):1816-1826. doi:10.1016/S0140-6736(19)32317-7Butt AK, Patel J, Shirwany H, Mirza Q, Hoover J, Khouzam RN.Beneficial extracardiac effects of cardiovascular medications.Curr Cardiol Rev. 2022;18(2):e151021197270. doi:10.2174/1573403X17666211015145132National Library of Medicine: MedlinePlus.Amiloride.Abdallah HM.New trends in pharmacological treatment of acute kidney injury.Asian Pac J Trop Biomed. 2021;11(7):285-97. doi:10.4103/2221-1691.317241Wang C, Xiong B, Cai L.Effects of tolvaptan in patients with acute heart failure: A systematic review and meta-analysis.BMC Cardiovasc Disord. 2017;17(1). doi:10.1186/s12872-017-0598-yTexas Heart Institute.Diuretics.Harvard Health Publishing.Tips for taking diuretic medications.Puga A, Lopez-Oliva S, Trives C, Partearroyo T, Varela-Moreiras G.Effects of drugs and excipients on hydration status.Nutrients. 2019;11(3):669. doi:10.3390/nu11030669Brater DC, Ellison DH.Mechanism of action of diuretics. In: Sterns RH, Emmett M, eds.UpToDate. UpToDate, 2024.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Kehrenberg MCA, Bachmann HS.Diuretics: a contemporary pharmacological classification?.Naunyn Schmiedebergs Arch Pharmacol. 2022;395(6):619-627. doi:10.1007/s00210-022-02228-0HCA Virginia Physicians.The truth about water pills and weight loss.American Academy of Ophthalmology.Acetazolamide: considerations for systemic administration.Simes BC, MacGregor GG.Sodium-glucose cotransporter-2 (SGLT2) inhibitors: a clinician’s guide.Diabetes Metab Syndr Obes. 2019;12:2125–2136. doi:10.2147/DMSO.S212003Oh SW, Han SY.Loop diuretics in clinical practice.Electrolyte Blood Press. 2015;13(1):17-21. doi:10.5049/EBP.2015.13.1.17UpToDate.Diuretics and calcium balance.Suchard MA, Schuemie MJ, Krumholz HM, et al.Comprehensive comparative effectiveness and safety of first-line antihypertensive drug classes: a systematic, multinational, large-scale analysis.Lancet. 2019;394(10211):1816-1826. doi:10.1016/S0140-6736(19)32317-7Butt AK, Patel J, Shirwany H, Mirza Q, Hoover J, Khouzam RN.Beneficial extracardiac effects of cardiovascular medications.Curr Cardiol Rev. 2022;18(2):e151021197270. doi:10.2174/1573403X17666211015145132National Library of Medicine: MedlinePlus.Amiloride.Abdallah HM.New trends in pharmacological treatment of acute kidney injury.Asian Pac J Trop Biomed. 2021;11(7):285-97. doi:10.4103/2221-1691.317241Wang C, Xiong B, Cai L.Effects of tolvaptan in patients with acute heart failure: A systematic review and meta-analysis.BMC Cardiovasc Disord. 2017;17(1). doi:10.1186/s12872-017-0598-yTexas Heart Institute.Diuretics.Harvard Health Publishing.Tips for taking diuretic medications.Puga A, Lopez-Oliva S, Trives C, Partearroyo T, Varela-Moreiras G.Effects of drugs and excipients on hydration status.Nutrients. 2019;11(3):669. doi:10.3390/nu11030669Brater DC, Ellison DH.Mechanism of action of diuretics. In: Sterns RH, Emmett M, eds.UpToDate. UpToDate, 2024.
Kehrenberg MCA, Bachmann HS.Diuretics: a contemporary pharmacological classification?.Naunyn Schmiedebergs Arch Pharmacol. 2022;395(6):619-627. doi:10.1007/s00210-022-02228-0
HCA Virginia Physicians.The truth about water pills and weight loss.
American Academy of Ophthalmology.Acetazolamide: considerations for systemic administration.
Simes BC, MacGregor GG.Sodium-glucose cotransporter-2 (SGLT2) inhibitors: a clinician’s guide.Diabetes Metab Syndr Obes. 2019;12:2125–2136. doi:10.2147/DMSO.S212003
Oh SW, Han SY.Loop diuretics in clinical practice.Electrolyte Blood Press. 2015;13(1):17-21. doi:10.5049/EBP.2015.13.1.17
UpToDate.Diuretics and calcium balance.
Suchard MA, Schuemie MJ, Krumholz HM, et al.Comprehensive comparative effectiveness and safety of first-line antihypertensive drug classes: a systematic, multinational, large-scale analysis.Lancet. 2019;394(10211):1816-1826. doi:10.1016/S0140-6736(19)32317-7
Butt AK, Patel J, Shirwany H, Mirza Q, Hoover J, Khouzam RN.Beneficial extracardiac effects of cardiovascular medications.Curr Cardiol Rev. 2022;18(2):e151021197270. doi:10.2174/1573403X17666211015145132
National Library of Medicine: MedlinePlus.Amiloride.
Abdallah HM.New trends in pharmacological treatment of acute kidney injury.Asian Pac J Trop Biomed. 2021;11(7):285-97. doi:10.4103/2221-1691.317241
Wang C, Xiong B, Cai L.Effects of tolvaptan in patients with acute heart failure: A systematic review and meta-analysis.BMC Cardiovasc Disord. 2017;17(1). doi:10.1186/s12872-017-0598-y
Texas Heart Institute.Diuretics.
Harvard Health Publishing.Tips for taking diuretic medications.
Puga A, Lopez-Oliva S, Trives C, Partearroyo T, Varela-Moreiras G.Effects of drugs and excipients on hydration status.Nutrients. 2019;11(3):669. doi:10.3390/nu11030669
Brater DC, Ellison DH.Mechanism of action of diuretics. In: Sterns RH, Emmett M, eds.UpToDate. UpToDate, 2024.
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