Maximum serum K+ concentration within 1 hour with enteral replacement in severe hypokalemia.

Introduction: we report two cases with severe hypokalemia. Patients and methods: a 68-year-old woman was admitted with lower limb swelling and urinary symptoms; on the fourth day serum K+ concentration (s[K+]) was 2.3 mmol/L. A 64-year-old woman was admitted with pain in the lumbosacral spine, she was diagnosed with multiple myeloma. After receiving specific therapy she showed s[K+] at 2.4 mmol/L. A KCl solution containing 26.8 mEq of K+ was administered enterally, which increased s[K+] by 0.7 mmol/L within 1 h. Results and conclusion: these cases reveal that peak s[K+] may be achieved within 1 hour after KCl intake in severe hypokalemia, which is probably faster than IV administration.