Measurement of Na+ levels in serum is used for diagnosis of fluid and electrolyte imbalance, disorders of acid-base balance or excessive sodium intake.

Reference Ranges

Adults:135 – 145 mmol/L
0 – 7 days133 – 146 mmol/L
7 – 31 days134 – 144 mmol/L
1 – 6 months134 – 142 mmol/L
6 months – 1 year133 – 142 mmol/L
> 1 year134 – 143 mmol/L
Each laboratory should check if the reference ranges are transferable to its own patient population and determine own reference ranges if necessary. For diagnostic purposes, the results should always be assessed with the patient’s medical history, clinical examinations and other findings.

For information on clinical relevance, please refer to the package insert.

Abnormal sodium values indicate edema, renal diseases (e.g. diabetes insipidus), endocrine diseases as hypothyroidism or SIADH (syndrome of inappropriate antidiuretic hormone secretion).


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