What is potassium deficiency?
Potassium deficiency is when a person has abnormally low levels of potassium in their body. It is also called hypokalaemia.
Potassium is a mineral that helps regulate fluid in the body and helps muscles and nerves to work properly. It is found inside cells and is essential for good health.
What are the symptoms of potassium deficiency?
If you have low levels of potassium, symptoms may include:
- feeling tired
- muscle cramps
- an abnormal heart rhythm (arrhythmia) – skipped heartbeats or an irregular heartbeat
- tingling or numbness
- increased urination
What causes potassium deficiency?
Hypokalaemia can happen if someone becomes dehydrated. Some medications can cause the body to lose potassium, such as diuretics (fluid tablets).
You are at risk of developing low potassium levels if you:
- have vomiting or diarrhoea
- have a very physically demanding job causing sweating
- live in extremely hot climates
- are a professional athlete
- are taking antibiotics
- have chronic kidney disease
- have an eating disorder such as bulimia
- have low magnesium levels in the body
- don’t get enough potassium from your diet (though this is very rare)
How is potassium deficiency diagnosed?
Potassium deficiency is diagnosed with a blood test. Your doctor may order a test as part of a routine medical examination, or because you have high blood pressure or kidney disease.
How is potassium deficiency treated?
If you have low potassium, your doctor may recommend you take a supplement. You should only take a potassium supplement under medical supervision, as having too much potassium in the body can also cause serious health problems. If your levels are very low, you may need potassium through a drip in hospital.
Your doctor may also adjust your medications, if they are causing the potassium deficiency, or recommend you eat more foods that are high in potassium.
What are the complications of potassium deficiency?
Someone with severe hypokalemia can experience:
- decreased brain function
- high blood sugar levels
- muscle paralysis
- difficulty breathing
- irregular heartbeat
Severe hypokalemia can be life threatening.
Can potassium deficiency be prevented?
Most people can prevent potassium deficiency by eating a healthy, balanced diet.
If you are at increased risk, for example if you are taking diuretics, talk to your doctor about your potassium levels.
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Last reviewed: April 2021