Hyperkalemia

Hyperkalemia is a condition where the potassium level in the blood is higher than normal, exceeding 5.6 mmol/L. Potassium is a vital electrolyte that plays a central role in regulating heart rhythm and muscle contractions. Normal potassium levels in the blood range between 3.5 and 5.0 mmol/L. Untreated hyperkalemia can lead to severe health complications, including death.

Hyperkalemia is one of the most acute electrolyte disturbances and often requires immediate attention. Although the condition can be life-threatening, it may sometimes occur without clear symptoms, making regular monitoring and early detection crucial, especially for individuals with underlying kidney disease or cardiovascular issues. Hyperkalemia is identified through blood tests that measure potassium levels.

Symptoms of Hyperkalemia

The symptoms of hyperkalemia vary depending on its severity and can sometimes be asymptomatic in mild cases. Common symptoms include:

  • Muscle weakness or paralysis: A sensation of weakness or lack of strength in the muscles.
  • Fatigue: General lethargy, exhaustion, dizziness, and nausea.
  • Irregular heartbeat (arrhythmia): Heart rhythm disturbances, which can be life-threatening in severe cases.
  • Tingling or numbness: A tingling or prickling sensation in the hands and feet.
  • Breathing difficulties: At very high levels, hyperkalemia can impair the respiratory muscles, causing shortness of breath.

Severe hyperkalemia can lead to cardiac arrest if not treated promptly. If you experience any of these symptoms in combination with high potassium levels, seek medical attention immediately, as hyperkalemia can result in life-threatening complications.

Causes of Hyperkalemia

Hyperkalemia can result from various causes, including:

  • Impaired kidney function: The kidneys regulate potassium balance by excreting excess potassium through urine. Kidney failure or disease can compromise this function, causing potassium levels to rise.
  • Medications: Certain drugs, such as ACE inhibitors, angiotensin II receptor blockers (ARBs), and some diuretics, can affect the kidneys' ability to excrete potassium.
  • Excessive potassium intake: Although relatively rare, consuming large amounts of potassium-rich foods or supplements can increase the risk of hyperkalemia, particularly in combination with reduced kidney function.
  • Hormonal imbalances: Conditions such as Addison's disease, where aldosterone production is low, can lead to hyperkalemia.
  • Cell or tissue damage: Severe injuries, such as burns or crush injuries, can release large amounts of potassium from the cells into the bloodstream.

What Happens in the Body During Hyperkalemia?

Hyperkalemia disrupts the body's electrical balance, potentially impairing the function of the heart and muscles. Elevated potassium levels, typically above 5.6 mmol/L, can cause the heart to struggle to maintain a stable rhythm, resulting in arrhythmias and, in severe cases, cardiac arrest. The nervous system and muscles may also be affected, leading to weakness or paralysis.

Who is at Risk of Hyperkalemia?

Hyperkalemia can affect anyone, but certain groups are at higher risk, including individuals with chronic kidney disease, diabetes, heart failure, or those taking medications that affect potassium handling by the kidneys. Older adults are also at greater risk due to age-related declines in kidney function.

Diagnosing Hyperkalemia

Diagnosis is made through blood tests that measure potassium levels. Additional tests may include:

  • Blood tests: Besides potassium, kidney function markers such as creatinine and Cystatin C are often measured to assess whether the kidneys are contributing to hyperkalemia.
  • EKG: An electrocardiogram is used to identify heart rhythm changes caused by elevated potassium levels.
  • Urine tests: These can help evaluate whether the kidneys are excreting sufficient potassium.

Treatment of Hyperkalemia

Treatment depends on the potassium level and the underlying cause of hyperkalemia. Common treatments include:

  • Acute treatment: Intravenous calcium can be administered to stabilize the heart, while insulin combined with glucose can rapidly lower potassium levels by shifting potassium into the cells.
  • Potassium-binding agents: These help remove excess potassium through the gastrointestinal tract.
  • Diuretics: Potassium-wasting diuretics can be used to increase potassium excretion through the kidneys.
  • Medication adjustments: If hyperkalemia is caused by medication, the dosage may need to be reduced, or the drug replaced.

Lifestyle Tips for Preventing Hyperkalemia

Preventing hyperkalemia often involves managing underlying conditions and making specific lifestyle changes. Tips include:

  • Dietary advice: Limit intake of potassium-rich foods if you have risk factors for hyperkalemia, particularly if kidney function is impaired.
  • Regular monitoring: Check potassium levels regularly if you are at risk, such as having kidney disease or taking medications affecting potassium.
  • Lifestyle choices: Maintain a balanced diet and adequate hydration, and avoid medications without consulting a healthcare provider.

Related tests and health checks

Kidney tests

Kidney tests


  • Measures your potassium level.
  • Indication for possible potassium deficiency
  • Insight into how your kidneys are doing.

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