ACE inhibitors require monitoring of which electrolyte due to common side effect?

• A. Sodium
• B. Calcium
• C. Magnesium
• D. Potassium

Answer: (D)

Blockade of angiotensin II with ACE inhibitors decreases aldosterone production. Aldosterone normally promotes potassium excretion in the distal nephron, so when its levels drop, potassium isn’t excreted as effectively and serum potassium can rise. This makes hyperkalemia a common and important side effect to monitor for with ACE inhibitors. Clinically, monitor potassium levels after starting or changing the dose, and be especially cautious in patients with kidney disease, the elderly, or those taking other potassium-sparing agents or supplements. While sodium and other electrolytes are important in overall health, the electrolyte most specifically prompted to be watched with this drug class is potassium, due to its direct link to reduced aldosterone and potassium retention.