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Electrolytes

Potassium

Electrolyte essential for heart rhythm, muscle function, and nerve signaling.

What is Potassium?

Potassium is tightly regulated and can be influenced by diet, medication, and kidney function. Even small shifts may be meaningful, so context and repeat testing can matter. It is often assessed alongside sodium and kidney markers.

Why is Potassium relevant?

Potassium is an electrolyte that is tightly regulated because it is critical for heart rhythm, muscle function, and nerve signaling. Even small deviations can be meaningful — which is why many labs use narrower reference ranges for potassium than for other markers. For people on diuretics, heart medication, or certain supplements, it is a marker worth tracking regularly.

How to read Potassium in context

Always read potassium alongside sodium, creatinine, and eGFR — kidney function determines how your body handles potassium. Hemolysis of the blood sample (cells breaking during or after the draw) can make potassium look artificially much higher; if a result is unexpectedly high, you almost always re-test. Symptoms like muscle weakness or palpitations add useful context to the value.

Potassium is one of 100+ biomarkers in the Optimize panel. Book a blood draw at any of 238+ partner labs in the Netherlands, or upload your existing results in the app.

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