Sodium
Also written as: Na
An electrolyte that tracks your body water balance.
What it measures
The concentration of sodium in blood. In practice it says more about the balance between salt and water in the body than about salt intake.
Why a doctor orders it
Included in metabolic panels, and checked when confusion, fluid problems, or medication effects are being considered.
What is generally associated with a higher result
Broadly associated with dehydration and insufficient water intake relative to losses.
What is generally associated with a lower result
Broadly associated with excess water relative to salt, some medications including certain diuretics and antidepressants, heart, liver and kidney conditions, and some hormonal conditions.
Everyday things that move this number
Not every shift in a value reflects disease. These are ordinary factors known to affect this particular measurement:
- Hydration
- Diuretics
- Recent heavy fluid intake
Questions to take to your appointment
- Is this a new change, and should it be rechecked?
Build a printable questionnaire with your own results →
Where to read more
MedlinePlus, from the US National Library of Medicine, publishes patient-facing pages on individual lab tests and is a reliable next stop: medlineplus.gov/lab-tests .
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