Potassium test 


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A potassium test measures the amount of potassium in blood serum (the fluid part of your blood).

Potassium is a mineral that has a number of uses including:

  • assisting in the communication between nerves and muscles
  • helping nutrients move into cells and waste products move out of cells
  • helping the heart to function healthily

A potassium test may be recommended to help diagnose or monitor kidney disease, which is the most common cause of high potassium levels.

Your doctor may also recommend the test if you have heart-related problems, such as high blood pressure (hypertension).

If you have low potassium levels, you may have a heart problem, such as an irregular heartbeat. If you have high potassium levels, your heart muscle activity may be reduced. Both situations are serious and can be life-threatening.

You may also have a potassium test if you have diabetes and your doctor thinks you may have diabetic ketoacidosis (a complication caused by a lack of insulin in the body).

In rare cases, potassium levels may be low through poor diet. Good sources of dietary potassium include:

  • fruit, particularly bananas
  • vegetables
  • pulses
  • nuts and seeds
  • milk
  • fish
  • shellfish
  • beef
  • chicken
  • turkey
  • bread

Read more about the potassium test at Lab Tests Online UK.

Page last reviewed: 21/11/2013

Next review due: 21/11/2015


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The 2 comments posted are personal views. Any information they give has not been checked and may not be accurate.

BusySuzi said on 28 June 2012

I've now had around 10 of these tsts as my potassium level is getting lower. Yesterday I was told it was 2.6 which apparently is dangerously low.
I have been given three courses of Potassium pills to take for 5 days and these were supposed to raise the level - not so! The symptons David, as I'm finding is excessive tiredness avove all. I have been told to eat plenty of potassium-rich foods such as bananas, tomatoes, legumes, and avocados but there's only so much you can fit into one day!

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David Gamon said on 17 October 2010

A potassium test is used to establish whether one has hyperkalaemia which is established by having a potassium test. That's little use. I want to know (briefly) what the symptoms or cure, if any, are. DG

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