How do we treat a case of hypercalcemia?

• Hydration with saline NS at 300–500 mL/hour Up to 3–4 L in first 24 hours

• Forced diuresis NS at 100–200 mL/hour

+ furosemide IV 20–40 mg BD/QID

S/E Potassium and Mg depletion Renal Ca calculi

Volume overload and pulmonary edema

• Bisphosphonates

Onset of action over 1–2 days Inhibits osteoclast action by complex mechanisms 2nd generation Pamidronate 30–90 mg in 500 mL NS/5%D over 4 hours 3rd generation Zoledronate 4–5 mg IV infusion over 30 min

S/E of infusion Fever in 20%

↓ Ca, P, Mg

• Calcitonin—2–8 U/kg SC/IM/IV every 6–12 hour

Onset of action within hours Tachyphylaxis after 24 hours of use Safe in renal failure Mechanism of action—blocks bone resorption via receptors on osteoclasts Inhibits renal tubular Ca reabsorption → ↑ urinary Ca excretion

Treatment approach

Mild hypercalcemia → 1

Severe hypercalcemia → 2 + 3 + 4

Intermediate hypercalcemia → 1 + 2/3/4.......