Sodium Test
- Category
- Electrolytes
- Sample
- Blood sample taken from a vein in your arm
- Reports () Terms & Conditions Report time varies with time of sample collection.
- In 2 days
- Fasting
- No Fasting
- Age
- 5+ Years
Measures sodium, the main electrolyte that controls water balance and nerve function.
Detects low sodium (hyponatraemia) — common in the elderly, with diuretics, vomiting or heart/liver/kidney disease — or high sodium from dehydration. Both can cause confusion, weakness or seizures.
Vomiting, diarrhoea, dehydration, weakness, people on BP medicines or diuretics, kidney or heart conditions.
No fasting needed.
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Diuretics and some antidepressants, excessive water intake, heart failure and hormonal problems are common causes.
No fasting is needed. You can eat and drink normally unless your doctor has advised otherwise.
Blood sample taken from a vein in your arm.
Usually within 11–35 hours after the sample reaches the lab. You will receive the report online.