Corrected Sodium for Hyperglycemia
Compute glucose-corrected serum sodium using both of the published correction factors so the clinician can see them side by side.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Measured sodium
- 130 mEq/L
- Glucose
- 600 mg/dL
Result: Corrected Na 138 (1.6); 142 (2.4)
The tool opens with these values already filled in. Replace them with your own.
What you enter
- Measured sodium
- Glucose
What this is
The classic Katz factor adds 1.6 mEq/L of sodium for every 100 mg/dL of glucose above 100; the Hillier factor (often called the 'true' correction, derived from a 1999 hyperglycemic-clamp study) adds 2.4 mEq/L per 100 mg/dL. Sophie Well takes the measured sodium and glucose and returns both corrected values along with the magnitude of the difference between them.
When to use it
Use this on any patient with hyperglycemia (DKA, hyperosmolar hyperglycemic state, severe hyperglycemia of any cause) where the measured sodium may be falsely low because glucose is osmotically drawing water into the vascular space and diluting the sodium. The corrected value, not the measured value, is what guides fluid choice and rate of correction. The 1.6 and 2.4 factors disagree most in profound hyperglycemia (glucose above 400); both are widely cited and most institutions default to one or the other - check your local protocol before acting on a marginal call.
How this is calculated
Katz MA. Hyperglycemia-induced hyponatremia. N Engl J Med. 1973;289(16):843-844. Hillier TA, Abbott RD, Barrett EJ. Hyponatremia: evaluating the correction factor for hyperglycemia. Am J Med. 1999;106(4):399-403. Read the sources: Katz 1973 (correction factor) ↗, Hillier 1999 (revised factor) ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.
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