What does this test include?
This panel measures sodium and potassium, two key electrolytes involved in fluid balance, nerves, muscles and heart rhythm. The values often need to be interpreted with kidney function and medicines.
Why might it be ordered?
- To assess fluid or electrolyte disturbance during illness.
- To monitor kidney, heart or hormone conditions and medicines such as diuretics.
What sample is needed?
A blood sample is required. The laboratory chooses the correct tube and handles the sample for this test.
How should you prepare?
Ask the laboratory whether you need to fast or attend at a particular time. Do not stop or change medicines or supplements unless your clinician tells you to.
How are the results reported?
Either value can require prompt attention when markedly abnormal. Sample haemolysis can falsely raise potassium, while glucose and hydration can alter sodium interpretation.
Sources and editorial status
This patient-facing text is an editorial draft. It should be approved by a laboratory physician before official publication.