How to increase your potassium for heart failure patients

Cardiology

What is potassium?

Potassium is a mineral found in most types of food.

It has many important uses in the body.

  • A normal potassium level is usually 3.5 - 5.3 millimoles per litre (mmol/L).
  • If you have reduced left ventricular function, normal potassium range is 3.9 - 5.3 millimoles per litre (mmol/L).

Why is my potassium level out of normal range?

The most common reason for potassium being out of range is that your kidneys are not working properly. The kidneys usually control the level of potassium in your blood and prevent it from becoming too low or high.

Medications can also affect potassium level including some medications used to treat heart failure. Diuretics or ‘water tablets’ (Furosemide, Bumetanide) and Thiazides (Metolazone, Bendroflumethiazide) can cause a drop in potassium.

If you are unsure why your potassium level is abnormal, you can discuss this with the Heart Failure Team.

Why is it important to keep potassium level in range?

A potassium level that is too low can cause problems with your heart such as cardiac arrhythmia (irregular heart rhythm) and in some cases, could cause a cardiac arrest (heart stops beating). Patients with heart failure are at higher risk of these happening, so it is vital to keep your potassium level in normal range.

How will my potassium level be monitored?

Potassium level is checked by blood tests. If your potassium level is out of the normal range, we may do blood tests more often to monitor this.

How can I keep my potassium in normal range?

Many foods and drinks contain potassium. We may ask you to alter your diet to increase the amount of potassium you are consuming.

Do not restrict or increase your potassium intake unless you are advised to do so.

Sando K tablets

Sometimes, you may be asked to take potassium supplement medication to increase your potassium level quickly. The supplement most commonly used for heart failure patients is Sando K tablets.

Sando K is not a long term medication except in rare cases. It is often given in short courses which are stopped after a couple of days. Do not take Sando K medication if you have not been advised to. It is important to only take the prescribed dose you have been asked to take and then stop, even if you have spare tablets left. The dosage and length of treatment will depend on your existing potassium level, and whether there is continuing potassium loss.

If you are unsure whether you should be taking Sando K or not, please contact the Heart Failure Team or your Doctor for further advice.

Diet

Changing your diet can help to bring your potassium level back to within the normal range. Nearly all foods contain potassium but some foods contain more than others. Eating small amounts of high potassium foods can increase the potassium level in your blood.

What food and drinks are high in potassium?

You should continue to eat your meals and snacks as usual but include some of the high potassium foods listed below. Each of these food portions contain a similar amount of potassium. Each portion provides around 10 mmo/L of potassium which is the same as one Sando K tablet.

Fruit

  • Banana - 1 medium
  • Apricots (dried) - 2 small
  • Dates (dried) - 2
  • Raisins - 4 tablespoons
  • Prunes (dried) - 5
  • Avocado - 1 small

Vegetables

  • Spinach (fresh) - 2 handfuls
  • Mushrooms (raw or fried) - 12 medium

Snacks

  • Potato crisps - 40g bag
  • Plain fruit cake - 1 average slice

Drinks

  • Milky coffee - 1 heaped teaspoon of coffee with 200ml milk
  • Concentrated orange juice - half a small glass (50ml)
  • Milk - 250ml
  • Instant hot chocolate - 4 heaped teaspoons of instant hot chocolate powder made up with water
  • Horlicks - 3 teaspoons of Horlicks with 150ml milk
  • Tomato juice - 1 small glass (175ml)
  • Tomato soup - 200g tin

To have with meals

  • Baked beans -  3 tablespoons
  • Chips - 6
  • Jacket potato (flesh and skin) - half a small potato
  • Kidney beans - 4 tablespoons
  • Tinned tomatoes - 130g (a third of a 400g tin)

Please note: some foods may not be suitable for diabetes control or diets for other health conditions. If you are diabetic or have any other dietary requirements, it is important you talk to the Heart Failure Team about this. You may need to be referred to a Dietitian.

How to contact us

Community Heart Failure Team

01709 423257
9am to 5pm, Monday to Friday
Please leave a message on the answerphone and a member of the team will call you back.
Messages may not be picked up until the next working day.

How to increase your potassium for heart failure patients - patient information leaflet
Revision due: January 2025
Version: 1

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