Why Are Diuretics Useful in the Treatment of Hypertension?

Hypertension, or high blood pressure, places people at increased risk of having a stroke, heart disease and kidney disease. Diuretics are often the first choice for treating patients with blood pressure that has not been controlled by diet and exercise.

How Diuretics Work

• Diuretics are often referred to as "water pills" because they increase urination. They work in the body by forcing the kidneys to put increased amounts of sodium into the urine.

Benefit for Hypertension

• The increased sodium levels in the urine require removal of larger amounts of water from the bloodstream. This decreases the level of fluid in the blood vessels, which also decreases the pressure placed on the walls of the arteries.

Types

• There are three main kinds of diuretics: loop acting, thiazide and potassium sparing. Thiazide diuretics are usually the first type given as part of a hypertension treatment plan. Loop-acting diuretics may also be used, but potassium-sparing diuretics do not work as well for controlling blood pressure.

Side Effects

• Potential side effects may include increased urination, hypokalemia (decreased potassium in the blood), increased blood sugar, rash, low blood sodium levels, increased cholesterol, impotence, menstrual abnormalities and gynecomastia (male breast enlargement).

Drug Interactions

• Other medications may interact with a diuretic, including certain antidepressants, lithium, other blood pressure medications and digitalis (which increases blood flow).