In a patient with heart failure, what medication should be withheld if the serum potassium level is 5.2?

In the context of managing a patient with heart failure, spironolactone is a potassium-sparing diuretic that can lead to increased serum potassium levels. When a patient's serum potassium level is 5.2 mEq/L, this is considered elevated, especially in the context of potassium management.

Spironolactone works by antagonizing the effects of aldosterone, which promotes the retention of potassium. In patients already experiencing mild hyperkalemia, administering spironolactone could worsen their potassium levels and potentially lead to serious complications, such as cardiac dysrhythmias. Thus, withholding spironolactone when potassium is elevated helps to prevent these risks.

The other medications listed have different profiles regarding potassium levels. Furosemide is a loop diuretic and can actually cause potassium depletion. Digoxin does not have a direct effect on potassium retention but requires caution with hyperkalemia as it can affect its efficacy and increase the risk of toxicity. Atenolol is a beta-blocker that does not influence potassium levels significantly. Each of these can be considered based on potassium levels and the overall clinical status of the patient, but spironolactone specifically should be withheld in the presence of elevated potassium due to its direct