Diuretics, commonly known as "water pills", are medications that promote the excretion of excess salt and water from the body through urine. They are primarily used to treat conditions associated with fluid retention and high blood pressure (hypertension). By increasing urine production, diuretics help reduce the volume of fluid in the blood vessels, which lowers blood pressure and decreases the workload on the heart.
There are three main types of diuretics: thiazide diuretics, loop diuretics, and potassium-sparing diuretics. Thiazide diuretics, such as hydrochlorothiazide, are often the first-line treatment for hypertension and work by inhibiting sodium reabsorption in the distal convoluted tubules of the kidneys. Loop diuretics, such as furosemide, are more potent and act on the loop of Henle in the kidneys, making them useful for treating severe edema associated with heart failure, liver cirrhosis, and kidney disease. Potassium-sparing diuretics, such as spironolactone, help retain potassium while promoting sodium and water excretion, making them useful in preventing hypokalemia, a common side effect of other diuretics.
Diuretics are also used to manage conditions like congestive heart failure, chronic kidney disease, and pulmonary edema by reducing fluid overload in the body. However, they must be used with caution as they can lead to electrolyte imbalances, such as low potassium (hypokalemia) or low sodium (hyponatremia), and dehydration if not monitored properly.
Patients taking diuretics are usually advised to have regular blood tests to monitor electrolyte levels and kidney function. Dietary adjustments, like increasing potassium intake for those on thiazide or loop diuretics, may also be recommended to counteract potential side effects.