High Potassium Information Sheet When your Kidney Function is Above 20

You have been referred to the kidney dietitians for support with your high potassium level. When the kidneys are not working properly, potassium can build up in the blood which can affect the rhythm of your heart. It is, therefore, important that the level of this mineral is kept at safe levels in the body. When your kidney function is above 20, your kidneys should be able to control the amount of potassium in your blood.

Often there are other possible causes that need to be explored before changing your diet.

Common causes of high potassium

Constipation
Having regular bowel movements helps to remove excess potassium from the body. Increasing the fibre content of your diet and ensuring you drink enough each day may help this. Sources of fibre include fruit, vegetables, wholegrains and pulses. If your bowels remain problematic, you may wish to speak to your doctor or pharmacist about a suitable laxative.

Certain medications, including supplements
Some medications can cause an increase in potassium levels. Speak with your doctor or pharmacist about this. Do not stop taking any medications unless you have been advised to do so by a healthcare professional.

Some foods and drinks
There is no specific diet you should be following; however, you should be aiming for a varied, balanced diet which is low in processed, convenience foods.

• Salt: avoiding both salt and reduced sodium alternatives such as Lo-Salt or Saxa, So-Lo etc in the diet.
• Vegetables: boiling vegetables and potatoes and throwing the water away helps to reduce their potassium content. Avoid steaming, microwaving or pressure cooking your vegetables and potatoes.
• Fruit: try to eat fruit in its natural form. Limit consumption of dried fruit, fruit juices and other processed forms of fruit. If consuming tinned fruit, be sure to drain off the juice/syrup it is tinned in.
• Processed, packaged foods such as ready meals, frozen convenience foods or savoury snack items can contain potassium-based additives which are easily absorbed by the body. Examples include potassium sorbate, potassium chloride, potassium phosphate. Look out for them on food packaging.
• Coffee: can contain high amounts of potassium. If you drink several cups a day, it may be worth trying to reduce this.

Muscle breakdown and rapid weight loss
If you are experiencing unplanned weight loss, please speak to your doctor/GP.

High blood glucose levels
Poorly controlled diabetes can increase the levels of potassium in your blood. It is, therefore, important to keep blood glucose levels within the recommended ranges. If you have diabetes and are struggling to control it, speak to your GP, practice nurse or diabetes team.

Dehydration
If you have recently been unwell and had an episode of vomiting or diarrhoea, this can cause dehydration which can increase potassium levels.

Developing acidosis
As kidney function declines, the body can find it harder to remove waste products from the body which can cause your blood to become more acidic. This can cause high potassium levels. This can be improved by oral bicarbonate medications and eating plenty of fruits and vegetables to reduce the acid and potassium levels.

Useful websites

Kidney Kitchen
kidneycareuk.org/get-support/healthy-diet-support/kidney-kitchen/

Kidney Care UK: High potassium levels (hyperkalaemia) and kidney disease
kidneycareuk.org/get-support/free-resources/patient-information-booklets/high-potassium-levels-hyperkalaemia-and-kidney-disease/

LiveWell Dorset
https://www.livewelldorset.co.uk/

About this leaflet

Authors: Olivia Chaffey, Joanna Pulman, Nicola Crockford, Kidney Dietitians
Written: April 2024
Approved: June 2024
Review date: June 2027
Edition: v1

If you have feedback regarding the accuracy of the information contained in this leaflet, or if you would like a list of references used to develop this leaflet, please email patientinformation.leaflets@dchft.nhs.uk