A 72-year-old patient with CKD Stage 4 (eGFR 22 mL/min/1.73m²) develops secondary hyperparathyroidism with PTH 450 pg/mL. Serum phosphate is 6.2 mg/dL. Which medication is preferred as a phosphate binder with the LOWEST risk of hypercalcemia?
- A Calcium carbonate
- B Sevelamer carbonate (non-calcium, non-aluminum) ✓
- C Aluminum hydroxide
- D Calcium acetate
Explanation
In CKD-MBD (Mineral Bone Disorder), sevelamer carbonate is the preferred non-calcium, non-aluminum phosphate binder. It avoids hypercalcemia caused by calcium-based binders (which also promote vascular calcification in CKD) and aluminum toxicity. KDIGO guidelines recommend restricting calcium-based binders in patients with hypercalcemia, vascular calcification, arterial stiffness, or adynamic bone disease. Sevelamer also lowers LDL cholesterol as a beneficial side effect. Aluminum hydroxide is effective but reserved for short-term use due to aluminum neurotoxicity with long-term use.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.