Water pills are generally considered safe, but a person's individual health needs must be taken into account to determine the drug's true benefits.
What Are Water Pills?
Harvard Health Publishing describes three types of water pills: loop diuretics, thiazide diuretics and potassium-sparing diuretics. Each type of diuretic affects a different part of your kidneys and has different uses, side effects and precautions. Harvard Health says the differentiations are:
- Loop diuretics act on a particular "loop" in the millions of tubules that make up the kidneys.
- Thiazide diuretics act on a different part of the kidney tubules but give the same result as loop diuretics. These diuretics cause the kidneys to increase the amount of salt and water in the urine. Both of these diuretics can deplete potassium levels, and this can increase the risk for abnormal heart rhythms.
- Potassium-sparing diuretics leave more potassium in the blood than the two other
types. However, this can cause potassium levels to become too high, which can
also cause irregular heart rhythms.
Who Needs Water Pills?
Harvard Health states that diuretics are often prescribed as a first-line treatment for high blood pressure. Water pills lower the volume of fluid in the bloodstream, reducing pressure on artery walls.
According to Cedars-Sinai, diuretics can be useful for people who are older or obese, who also have congestive high blood pressure, swelling or water retention (edema) or heart failure. They may also be prescribed for certain kinds of kidney or liver disease. In addition, the Office of Women's Health suggests water pills as a treatment for premenstrual syndrome (PMS) symptoms like bloating and breast tenderness.
Don't forget to consult your doctor before taking water pills. Cedars-Sinai recommends that, if diuretics are prescribed or recommended, the doctor should be made aware of any other drug, vitamin, mineral or herbal supplement the patient is taking. These include but aren't limited to:
- Other medications for high blood pressure
Because diuretics can worsen or negatively affect patient health, people who have the following health issues should make their doctors aware of their condition before taking diuretics:
- Tendency to become dehydrated easily
- Allergies to other medicines
- Pregnant (or considering becoming pregnant)
- Gout (or at high risk of developing gout)
- Kidney problems
Side Effects of Water Pills
Mayo Clinic writes that diuretics are generally safe, but that they do have side effects like increased urination and mineral loss and can affect blood potassium levels. If you take a potassium-sparing diuretic, you can develop too much potassium, which is called hyperkalemia. If you take a thiazide diuretic, you run the risk of developing a low level of potassium in your blood which is called hypokalemia.
Other side effects listed by Mayo Clinic include:
- Low sodium in your blood (hyponatremia)
- Muscle cramps
- Joint disorders (gout)
Risk of Abuse
Two populations are most at risk for abuse of water pills: those with eating disorders and athletes. Patients with eating disorders who abuse water pills do so because these drugs rid the body of excess sodium and water, which results in weight loss.
According to the National Eating Disorders Association, diuretic abuse can result in hypokalemia and contraction alkalosis. This means having a low blood potassium level and increased blood pH. In extreme cases, diuretic abuse can cause renal failure.
In a landmark September 2010 study published in the British Journal of Pharmacology, researchers found that athletes are at risk of diuretic abuse for two reasons: Water pills can be used to excrete water for rapid weight loss and to mask the presence of other banned substances.
- Texas Heart Institute: "Diuretics"
- Mayo Clinic: "Diuretics"
- Harvard Health Publishing: "What You Need to Know About: Diuretics"
- Cedars-Sinai: "Diuretic Drug Therapy"
- National Eating Disorders Association: "What All Medical Professionals Should Know About Eating Disorders"
- British Journal of Pharmacology: "The Abuse of Diuretics as Performance-Enhancing Drugs and Masking Agents in Sport Doping: Pharmacology, Toxicology and Analysis"
- Office on Women's Health: "Premenstrual Syndrome (PMS)"