Evidence
Original publication
Katz MA. Hyperglycemia-induced hyponatremia — calculation of expected serum sodium depression. Estimated that serum sodium falls by ~1.6 mmol/L for every 100 mg/dL rise in glucose above normal, from the osmotic shift of water into the extracellular space.
New England Journal of Medicine, 1973
Validation
Hillier TA, Abbott RD, Barrett EJ. Hyponatremia: evaluating the correction factor for hyperglycemia. A hyperglycaemic clamp study found a correction factor closer to 2.4 mmol/L per 100 mg/dL, especially at glucose > 400 mg/dL.
American Journal of Medicine, 1999
Last reviewed: 2026-09
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