Nephrology

Sodium Deficit (Hyponatraemia)

Estimated sodium needed to reach a target.

Education and reference only. Not a substitute for clinical judgement, local policy or product labelling. Always verify before clinical use. Values are calculated in your browser and never stored.

When to use

Use in hyponatraemia to estimate the sodium needed to raise serum sodium to a chosen target.

Why use

It gives a starting estimate to plan safe correction.

Critical actions

Correct slowly — generally raise serum sodium by no more than 8–10 mmol/L in 24 hours to avoid osmotic demyelination. This is an estimate; reassess sodium frequently.

Evidence & references

  1. Adrogué HJ, Madias NE. Hyponatremia. NEJM. 2000.

Related calculators

Free Water DeficitEstimated water deficit in hypernatraemia.Sodium Correction for HyperglycaemiaCorrected sodium in hyperglycaemia (Katz).Calculated Serum OsmolalityEstimated osmolality from electrolytes.

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