Final answer:
Spironlactone is a potassium-sparing diuretic that prevents potassium loss by antagonizing aldosterone action in the kidneys.
Step-by-step explanation:
Spironlactone (Aldactone) is a potassium-sparing diuretic. Diuretics are a class of drugs that promote diuresis, that is, the increased production of urine. Potassium-sparing diuretics like spironlactone are different from other diuretics in that they do not promote the secretion of potassium into the urine. Instead, they help to prevent the loss of potassium, which can be a side effect of other types of diuretics. Spironlactone works by antagonizing the effects of aldosterone, a mineralocorticoid hormone that increases the reabsorption of sodium and water and the release of potassium. By blocking aldosterone, spironlactone reduces sodium reabsorption and helps to keep potassium levels from decreasing.