Calcium gluconate is used in hyperkalemia to achieve which therapeutic effect?

• A. Increase serum potassium
• B. Stabilize cardiac membranes
• C. Increase insulin release
• D. Decrease urinary potassium excretion

Answer: (B)

Calcium gluconate works by stabilizing the heart’s electrical membranes when potassium is high. It raises the threshold for depolarization, making cardiac cells less excitable, which helps prevent dangerous arrhythmias that hyperkalemia can trigger. It does not lower the potassium level itself; other treatments are needed to shift potassium into cells or remove it from the body. The effect is rapid but temporary, buying time to implement measures like insulin with glucose, beta-agonists, bicarbonate, or dialysis as appropriate.