How is potassium separated from its compounds

potassium (K, K +)

Potassium is a mineral that plays a key role in the functioning of all cells in the body and nerves and muscles in particular.

Short version:

  • Potassium is of central importance for the energy metabolism.
  • Potassium can be found in many foods, so the daily potassium requirement is usually well covered with a balanced diet.
  • The potassium values ​​are determined in the blood serum and in the urine.
  • Far too high or far too low potassium levels are dangerous.

What is Potassium

Potassium is the most important mineral inside the cells. It creates the conditions for information to be passed from cell to cell.

Potassium is responsible for regulating the water balance, the acid-base balance and blood pressure (lowering blood pressure). As a component of digestive juices, potassium is also important in the gastrointestinal tract. It plays an important role in the transmission of electrical impulses to muscle and nerve cells and the heart.

The body strictly regulates the potassium level. If too much or too little potassium is present, the muscles may malfunction. Together with sodium, potassium is also important for the functioning of the heart muscle.

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What does potassium contain?

Potassium is absorbed through food. Since many foods contain potassium, the need is usually met with a balanced diet. It is recommended that you consume at least 2 grams of potassium daily.

Good sources of potassium are:

  • Bananas
  • Potatoes
  • Dried fruit (apricots, raisins, dates)
  • Mushrooms
  • Legumes (lentils)
  • Soy products
  • Wheat bran
  • orange juice
  • whole grain products
  • Nuts (almonds, pistachios)
  • flesh

How are potassium levels determined?

Potassium is determined in the blood serum and in the urine (see urine test). You can find unnaturally high potassium levels in the blood test if the arm is blocked for too long (see blood test). In addition, the blood cake must be separated from the serum within an hour. The reason for these potential sources of measurement error is the fact that potassium is about 25 times more concentrated in the erythrocytes than in the serum, and a breakdown of the erythrocytes (hemolysis) leads to the unnaturally high values ​​in the sample.

Reference / normal values

  • Adults: 3.6-4.8 mmol / l SI unit
  • Newborns: 3.6–6.1 mmol / l SI unit

Causes of low potassium levels

In the case of losses through the kidneys and hormonal disorders:

For losses via the gastrointestinal tract:

In case of distribution disorders:

  • Alkalosis (fluctuations in the acid-base balance)
  • Intestinal diseases such as ulcerative colitis or celiac disease (gluten intolerance)

What are the symptoms of a potassium deficiency?

  • Symptoms of paralysis of the muscles
  • constipation
  • Conduction disorders of the heart

How is a potassium deficiency treated?

An undersupply of potassium can usually be compensated for quickly and easily by consuming foods with a high potassium content. Potassium supplements should only be taken on medical advice, as these can also lead to a dangerous excess of potassium.

Causes of increased potassium levels

In case of kidney dysfunction (acute kidney failure, chronic kidney failure) or adrenal insufficiency:

Use of certain medications:

  • so-called potassium-sparing diuretics such as amiloride and triamterene
  • Antihypertensive agents such as ACE inhibitors, renin inhibitors, and sartans
  • Aldosterone antagonists such as spironolactone
  • Beta blockers
  • Succinylcholine
  • Heparin
  • Digoxin
  • Cytostatics etc.

In case of distribution disorders:

  • Hemolysis, massive cell breakdown (injuries, burns, after an operation)
  • Acidosis

What are the symptoms of high potassium levels?

A severe oversupply of potassium in the blood (hyperkalaemia) can lead to cardiac arrhythmias up to and including heart failure. It is a medical emergency!

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Dr. med. Iris Hertle (first author 2014), Silke Brenner (2018)
Medical review:
Dr. Thomas Schwingenschlögl
Editorial editing:
Andreas Lenz, Astrid Leitner

Status of medical information:

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