Potassium 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 potassium, an electrolyte critical for heart rhythm, muscles and nerves.
Detects high or low potassium, which can cause dangerous heart rhythm changes. Important for people with kidney disease or on BP medicines, diuretics or insulin.
Vomiting, diarrhoea, dehydration, weakness, people on BP medicines or diuretics, kidney or heart conditions.
No fasting needed.
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Yes. Delayed processing or difficult blood draws can falsely raise potassium, so an unexpected result may be repeated.
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.