All tests · Electrolytes & Minerals · Sodium (Na⁺)

Above the range

What causes a high Sodium (Na⁺)?

Normal range 135-145 mEq/L (135-145 mmol/L SI). Specimen: Serum or plasma. See the full Sodium (Na⁺) reference page for critical values and nursing considerations.

Above the range

Common causes of a high Sodium (Na⁺)

  • Water loss / dehydration
  • Diabetes insipidus
  • Excess sodium intake
  • Hyperaldosteronism

Looking for the other direction? See what causes a low Sodium (Na⁺).

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.

Sodium (Na⁺) reference range and specimen details
SpecimenSerum or plasma
Conventional range135-145 mEq/L
SI range135-145 mmol/L
Critical value< 120 or > 160 mmol/L (seizure and neurologic risk)
PanelElectrolytes & Minerals

Full details, including nursing considerations, on the Sodium (Na⁺) normal range page. Reference ranges vary by laboratory, method, age, sex, and population - always use the range printed on the actual result.

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