What are Potassium-Sparing Diuretics?

Potassium-sparing diuretics are diuretic drugs that treat water retention by increasing the amount of fluid excreted by the kidneys as urine. They work by stimulating the kidneys to remove more sodium from the body, to treat water-retention-related conditions such as hypertension. When more sodium is excreted, more water is as well, becausee sodium binds to water on a molecular level. There are three kinds of diuretics for water retention: potassium-sparing, loop, and thiazide. Potassium-sparing diuretics help the kidneys to excrete more fluids without also excreting too much of the body's potassium.

Diuretics are most commonly used to treat hypertension and hypertension-related heart problems. Diuretics can treat hypertension, or high blood pressure, because the excretion of excess fluids from the body reduces total blood volume within the body. When blood volume goes down, so does blood pressure, as there is simply less blood flowing through the circulatory system. Some diuretics can also be used to treat polycystic ovary syndrome, some kidney disorders, edema or tissue swelling, diabetes, and osteoporosis.

Some diuretic medications, such as loop diuretics and thiazide diuretics, stimulate the kidneys to produce more urine and excrete retained water from the body. These diuretics, however, also cause the body to lose potassium. Some patients may need medications that do not cause the body to lose potassium, depending on their medical history and use of other prescription drugs. Those who suffer from hypokalemia, or low blood potassium levels, for instance, cannot generally afford to lose more potassium from their bodies. For these patients, potassium-sparing diuretics stimulate the kidneys to excrete more urine without causing potassium loss as well.

Potassium-sparing diuretics are usually available only by prescription and include drugs such as triamterene, amiloride, and spironolactone. Dosages may vary according to the needs of the patient. Conditions such as kidney or liver disease, diabetes, gout, kidney stones, or menstrual problems will generally need to be taken into medical consideration before potassium-sparing diuretics can be prescribed and used.

Like many other prescription and over-the-counter drugs, potassium-sparing diuretics should typically not be used in combination with certain other medications. Patients are usually advised to discuss their use of prescription and over-the-counter drugs with their doctors before taking potassium-sparing diuretics or any other medical treatments.

Side effects of potassium-sparing diuretics can include dizziness, headache, nausea, vomiting, and stomach cramps. Some potassium-sparing diuretics may cause sensitivity to sunlight and all may increase the risk of hyperkalemia, or high blood potassium levels.