Which of these parameters should a nurse plan to monitor for a client who is receiving spironolactone (Aldactone)?

• A. Body weight
• B. Heart rate
• C. Urine (acetone) level
• D. Pulse oximetry

Answer: (A)

Spironolactone is a potassium-sparing diuretic that blocks aldosterone, promoting fluid loss while conserving potassium. The main way a nurse tracks how the drug is affecting the patient’s fluid status is by monitoring body weight. Daily weights provide a sensitive, practical measure of changes in extracellular fluid: if weight decreases, it often indicates effective diuresis and edema reduction; if weight rises or fails to decrease, it can signal fluid retention or overdiuresis.

Other choices don’t directly reflect the drug’s effect on fluid balance. Heart rate can vary for many reasons and isn’t a primary indicator of spironolactone response. Urine acetone isn’t related to this therapy, and pulse oximetry monitors oxygenation, not the diuretic’s impact.

In practice, you’d also monitor laboratory values, especially potassium and kidney function, because spironolactone can raise potassium levels and affect renal function, but among the given options, daily body weight best captures the patient’s response to the diuretic.