The Importance of Potassium in Kidney Dialysis

Potassium is very important for normal health. The potassium ion, the electrolyte K+, is involved in nerve and muscle communication systems - effectively it helps pass the nerve signals along. This includes to the heart, your most important muscle. It is also involved in many cellular processes (it's the major cation present in cells), involved in metabolism including carbohydrates, and is required for the proper operation of your cells, tissues and most organs. It is involved in the synthetic pathway that leads to proteins. And several other things too. Clearly an important mineral. Too much or too little can cause you problems.


Your kidneys would normally remove excess potassium from the body, so anything which hinders the normal operation of the kidneys can lead to hyperkalemia - a higher than normal potassium level in the blood. (Renal failure is the most common cause of hyperkalemia). The hormone aldsoterone controls the removal of potassium and the re-adsorption of sodium and water, so anything that can impair the production of this hormone (such as Addison's disease) will also affect potassium levels. The hormone is produced in the adrenal cortex in the adrenal gland. Serious tissue damage, such as a serius injury or burns or surgery causes the cells in your body to release potassium, increasing the problem. (Normal kidneys can handle the rise in potassium levels caused by such tissue damage, of course.) Some medicines can lead to increased potassium levels, but it is very unlikely that a dialysis patient would be prescribed these.

It is vital to know that hyperkalemia can lead to cardiac arrest, so this is why potassium levels are so important for dialysis patients. The electrical impulses that control the heart are interfered with when you suffer from hyperkalemia.

Hyperkalemia is not easy to detect, apart from making a visit to the doctor for a check-up and a potassium blood test. For a person on dialysis, regular blood tests are a more normal thing to have, so it can be picked up this way. But some symptoms that may indicate you may have a problem with your potassium levels include:-

Potassium in Food

But apart from medical problems, your diet can result in raised potassium levels. Reducing your potassium intake and taking diuretics (under medical supervision of course!) can help control the problem. Something definately to be avoided by renal failure patients are salt substitutes (these contain potassium instead of sodium and are a real no-no).

So the question most people want answered is which foods are high in potassium (almost all food contains some potassium).

There are a lot of vegetables to avoid, but research has shown that if you slice vegetables thinly, boil them for a while and discard the water, a fair bit of the potassium is leached out.

If you are on hemodialysis, potassium-rich foods are a big problem, as the potassium levels build up steadily between treatment sessions. It's less of a problem for those on peritoneal dialysis, as the daily routine helps keep your potassium levels a bit more under control, although this does not mean you can ignore potassium. This is why renal failure patients usually consult a renal dietician for specific advice about their condition.

But always remember - no web site is a substitute for proper medical advice from your own doctor. We are here to supplement, not to replace your medical advisor.