Which medication is known to put clients at risk for both hyperkalemia and hyponatremia when receiving diuretic therapy?

Spironolactone is a potassium-sparing diuretic that works by antagonizing the action of aldosterone in the distal nephron, leading to increased sodium and water excretion while conserving potassium. This mechanism significantly contributes to the risk of hyperkalemia because the medication allows potassium to remain in the body instead of being excreted.

Additionally, because spironolactone promotes the excretion of sodium, it can lead to hyponatremia as there is a loss of sodium in the urine. Hyponatremia occurs when the sodium levels drop below normal due to this enhanced urinary loss, especially in the context of diuretics which generally tend to promote net fluid movement and electrolyte imbalances.

The distinction between this medication and others like hydrochlorothiazide and furosemide is crucial. While these can cause electrolyte imbalances, they do not typically lead to hyperkalemia. Mannitol, being an osmotic diuretic, primarily affects osmotic balance rather than specifically potassium or sodium retention. Thus, spironolactone is specifically associated with both hyperkalemia and hyponatremia in clinical settings, confirming it as the correct choice in this scenario.