Convert any Sodium (Na⁺) result between units on the unit converter.
What is the normal range for Sodium (Na⁺)?
The standard teaching reference range for Sodium (Na⁺) is 135–145 mEq/L in conventional units, or 135–145 mmol/L in SI units. This value is measured in serum or plasma.
A commonly taught critical (panic) value is < 120 or > 160 mmol/L (seizure and neurologic risk). Critical results are reported to the provider immediately under your facility's policy.
Source: Adult reference values compiled from Pagana & Pagana, Mosby's Diagnostic and Laboratory Test Reference, and Fischbach & Dunning, A Manual of Laboratory and Diagnostic Tests. Reference ranges vary by laboratory, method, age, sex, and population — always use the range printed on the actual result.
Above the range
Common causes of a high Sodium (Na⁺)
Water loss / dehydration
Diabetes insipidus
Excess sodium intake
Hyperaldosteronism
Below the range
Common causes of a low Sodium (Na⁺)
SIADH
Heart failure or cirrhosis (dilutional)
Diuretics
Excess water intake
At the bedside
Nursing considerations
Correct chronic hyponatremia slowly to avoid osmotic demyelination.
Watch for neurologic changes — confusion, seizures — at either extreme.
Assess fluid status; sodium disorders are usually water problems.