Kidney system

Sodium

Na

The primary extracellular electrolyte — tightly regulated by kidneys and hormones.

What is it

Sodium — in plain English.

Sodium is the main electrolyte in extracellular fluid and is essential to fluid balance, nerve function, and blood pressure regulation.

Why it's measured

What Na can reveal.

Sodium levels have been used in clinical evaluation of hydration, kidney function, and hormonal balance in research and practice.

Reference range

Where most laboratories draw the standard line.

Standard laboratory reference

136 – 145 mEq/L

Reference ranges vary by laboratory. Your individual reference range will appear on your test report and should be interpreted by your physician in the context of your overall health profile.

What results may indicate

Higher vs. lower Na — at a high level.

Elevated

Has been associated with dehydration and certain endocrine conditions in research literature.

Lower

Has been associated with overhydration, kidney issues, and certain medications in research literature.

These associations are general. They are not a personal diagnosis or prediction. Discuss your individual results with your physician in the context of your full health profile.

When it's measured

When Na is typically run.

Part of standard electrolyte panels.

Related markers

Often measured alongside Na.

Measured in

Na is one of 160 biomarkers in the Apex Panel.

A complete look at your heart, hormones, metabolism, inflammation, and longevity systems — drawn at Quest or LabCorp, reviewed by a U.S.-licensed physician.

Explore the Apex Panel
160 biomarkers13 body systemsPhysician-reviewed
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This information is for general educational purposes only and is not medical advice. Lab results alone are not intended to diagnose, treat, or cure any condition and do not replace the advice of a healthcare provider. OPTML does not offer medical advice, a diagnosis, medical treatment, or any form of medical opinion.