In a patient with cirrhosis and ascites, which diuretic is commonly used as first-line therapy?

• A. Spironolactone
• B. Furosemide
• C. Mannitol
• D. Hydrochlorothiazide

Answer: (A)

In cirrhosis with ascites, excess aldosterone from secondary hyperaldosteronism drives sodium and water retention. The best first-line diuretic is spironolactone, a potassium-sparing mineralocorticoid receptor antagonist that blocks aldosterone’s effects in the collecting ducts. By counteracting aldosterone, it promotes sodium excretion while preserving potassium, addressing the root cause of fluid accumulation. If needed, furosemide can be added to enhance diuresis, but spironolactone alone targets the underlying pathophysiology. The other diuretics listed don’t specifically counteract aldosterone-driven Na retention and are not first-line in this setting.