Insight into your potassiumlevel.
Potassium is an electrolyte found mainly inside the cells that plays a role in the signal conduction of muscles and the heart. A test gives insight into the potassium level in your blood.
Also known as: K, electrolytes
Interpreted by BIG-registered doctors
How Bloodworks works
Order online
Choose your package and preferred location
Receive your lab form
Within 24 hours by email, with appointment planner
Schedule your blood draw
Or choose a walk-in location
Blood draw
Takes just a few minutes
Receive your report
Securely, within a few working days from our physicians
Background
What is potassium?
Potassium is an electrolyte located mainly inside the cells. The difference in potassium inside and outside the cell makes signal conduction possible. Potassium therefore plays a role in the contraction of muscles and in the rhythm of the heart. Only a small part of the body's potassium is in the blood, and it is precisely that part which this test measures.
The kidneys are the most important organ for regulating potassium. With reduced kidney function, potassium can accumulate. Medicines also play a role: diuretics can lower or raise the potassium level depending on the type, and widely used blood pressure medicines can raise the value. Because potassium is involved in cardiac signal conduction, the value is monitored more often with this medication.
In brief
Inside the cells
Most potassium is located within the cells
Signal conduction
Important for muscles and for the heart rhythm
Regulated by the kidneys
Kidney function helps determine the potassium level
Sensitive to the draw
Tourniquet time or cell damage can falsely raise the value
Common reasons to test
When can insight into your Potassium be valuable?
Below are some situations in which measuring Potassium can provide insight.
Insight into your potassium level
Potassium is a common first step in assessing the electrolyte balance, often together with sodium.
With diuretic use
Diuretics can lower or raise the potassium level depending on the type. Potassium is monitored more often with this medication.
With blood pressure medication
Widely used blood pressure medicines can raise the potassium level. Insight into the value is then relevant.
With reduced kidney function
The kidneys excrete potassium. If they work less well, potassium can accumulate. A test gives insight into this.
With questions about muscle function
Potassium plays a role in the signal conduction of muscles. The value is therefore sometimes taken into account with complaints of muscle weakness.
Tracking a value over time
For electrolytes the development over time is often more informative than a single measurement. Re-testing makes a change visible.
What your result means
How do we read your Potassium level?
Potassium is measured in millimoles per litre (mmol/L). The laboratory states the reference values that apply there alongside your result. Important: kidney function, medication use and the conditions during the blood draw can influence this value.
A low value
A low potassium level is seen with the use of certain diuretics, with prolonged vomiting or diarrhoea, and with hormonal causes. Because potassium is involved in the signal conduction of muscles and the heart, a low value is taken seriously. Our doctor explains what your value means and whether re-testing or follow-up via your GP is customary.
A normal value
A potassium level within the laboratory's reference values gives a reassuring picture at this moment. It remains a snapshot. If you use medicines that influence the potassium level, the development over time is often more informative than a single measurement.
An elevated value
An elevated potassium level may point to reduced kidney function or to the use of medicines that retain potassium, such as certain blood pressure medicines. There is also a common technical explanation: if the blood is constricted for a long time during the draw, or if cells break down in the tube, potassium leaks from those cells and the measured value is falsely raised. Re-testing is then customary. Our doctor assesses which explanation fits your situation.
How we interpret your result
Our doctors interpret your potassium level against the laboratory's reference values and your personal context, such as kidney function, medication use, lifestyle and any known conditions.
Related tests
Often combined with Potassium.
A single marker gives one perspective. For a broader picture you can combine Potassium with a theme package or related markers.
Frequently asked questions
Everything you want to know
Do I need to fast for a potassium test?
No, you do not need to fast for potassium. The conditions during the draw do matter, and our phlebotomist takes care of that.
Why can my potassium level be falsely raised?
Potassium is located mainly inside the cells. If the arm is constricted for a long time during the draw, or if cells break down in the tube, potassium leaks into the plasma and the laboratory measures a value that is too high. This is called haemolysis. If that is suspected, re-testing is customary.
What is the difference between potassium and sodium?
Potassium is found mainly inside the cells and plays a role in the signal conduction of muscles and the heart. Sodium is found mainly in the fluid outside the cells and helps determine the fluid balance. They are often measured together because the kidneys regulate both.
Which medicines influence my potassium level?
Diuretics can lower or raise the value depending on the type. Widely used blood pressure medicines can raise the potassium level. Please mention your medication with your result, so the doctor can take it into account.
Does my potassium level say anything about how much potassium I eat?
Only to a limited extent. With healthy kidney function, the kidneys excrete excess potassium and the blood level stays fairly stable, even with varying intake. The value therefore says more about regulation by the kidneys and about medication use than about your diet.
Is a single abnormal value immediately worrying?
Not necessarily. A single measurement is not a diagnosis, and with potassium a technical cause of a result that is too high is not unusual. The doctor looks at your context and advises whether re-testing is useful.
How often should I have potassium measured?
A single measurement is enough for initial insight. With the use of diuretics or blood pressure medication, with reduced kidney function, or with a previously abnormal value, periodic re-testing is customary.
What do I do with my result?
You receive a PDF report with your value and personal explanation. What you do with it, such as discussing it with your GP, remains entirely your choice.
Ready for insight into your potassium level?
For €49 you receive your potassium level including personal explanation from a doctor, typically within a few working days. No referral required.
Order Potassium for €49 →Want to test multiple markers at once?
Combine Potassium with other markers via Bloodworks Select. Blood draw costs are waived from €225.
49,-
All-in, blood draw included