A patient with CKD stage 4 (eGFR 22 mL/min/1.73 m²) has serum potassium 5.8 mEq/L. He is on ACE inhibitor (lisinopril 20 mg) and spironolactone. After stopping spironolactone, his potassium remains 5.8 mEq/L despite dietary restriction. Which potassium binder has demonstrated long-term efficacy and safety for hyperkalemia in CKD, allowing ACE inhibitor continuation?
- A Sodium polystyrene sulfonate (Kayexalate)
- B Patiromer or sodium zirconium cyclosilicate (SZC) ✓
- C Calcium resonium (calcium polystyrene sulfonate)
- D Activated charcoal
Explanation
Patiromer (a potassium-binding polymer that exchanges calcium for potassium in the GI tract) and sodium zirconium cyclosilicate (SZC, which selectively traps K+ ions in an inorganic crystal structure) are approved novel potassium binders with demonstrated safety and efficacy for chronic hyperkalemia in CKD, allowing continuation of RAAS inhibitors. OPAL-HK (patiromer) and HARMONIZE (SZC) trials showed significant and sustained potassium reduction. Sodium polystyrene sulfonate (Kayexalate) has serious concerns about intestinal necrosis and is no longer recommended for chronic use per contemporary guidelines.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.