Metabolic panel
Potassium
Potassium helps nerves fire and muscles contract, including the heart. The body keeps it within a narrow range, which is why results outside that range are taken seriously.
Typical adult reference range
Roughly 3.5 to 5.0 · mmol/L
Ranges vary between laboratories and by age, sex and method. Always read your own result against the range printed on your own report.
What a high result can mean
A high potassium can come from reduced kidney function, from medicines including some blood pressure treatments, and from supplements. It is also very commonly a false result caused by red cells breaking during a difficult blood draw, which releases potassium into the sample.
What a low result can mean
A low potassium can follow vomiting, diarrhoea, diuretic medicines, and some hormonal conditions. Marked lows can cause muscle weakness, cramps, and heart rhythm disturbance.
What commonly affects this result
How difficult the blood draw was, delay before the sample reached the lab, diuretics, and kidney function.
Questions worth asking your doctor
- Could this be a sample problem rather than a real result?
- Should it be repeated, and how urgently?
- Do any of my medicines push my potassium in this direction?
See what your own results say
Upload your blood test and get a plain English summary of every value on it, with the questions worth raising at your next appointment.
Analyse my resultsThis page explains what a test measures. It is general information, not medical advice, and it cannot tell you what your own result means. Reference ranges differ between laboratories, and results are only meaningful alongside your history, your symptoms and your other results. Always discuss your results with your doctor.