What is the action of potassium-sparing diuretics?

Potassium-sparing diuretics are a particular class of diuretics that are designed to conserve potassium rather than promoting its excretion from the body. Their primary mechanism of action involves inhibiting sodium reabsorption in the kidneys, particularly at the distal convoluted tubule and collecting ducts. By blocking the effect of aldosterone or directly inhibiting sodium channels, these diuretics facilitate the elimination of sodium and water, while allowing potassium to be retained. This is especially important in patients who may be at risk of hypokalemia—low potassium levels—due to the use of other diuretics that do promote potassium loss. As a result, potassium-sparing diuretics play a crucial role in managing conditions like hypertension and heart failure while helping to maintain electrolyte balance.