Elevated Potassium levels (Hyperkalaemia)

What is Hyperkalemia and what causes it?

Kalemia, is a measure of potassium concentration in the plasma. This normally ranges from 3.6 to 5 mmol/liter. Kidney disease, and use of certain medications, can cause excessively high serum potassium level (above 5.0 mmol/liter). This is called hyperkalemia, a common electrolyte abnormality. Potassium is involved in nerve transmission, muscle contraction, and kidney function.

Hyperkalemia most often results from increased amounts of potassium intake combined with impaired kidney function. Disorders affecting the kidneys decrease kidney excretion and are the most frequent cause of hyperkalemia. Healthy kidneys have can maintaining normal potassium levels even with high intakes by excreting potassium. However, the ability of kidneys with reduced function to adapt to rapid changes in potassium load, is impaired. Such rapid changes can be caused by eating a lot of potassium rich food. Potassium-rich foods include oranges, bananas, cantaloupes, apricots, peaches, papaya, avocados, potatoes, nuts, beans and chocolate. Some salt substitutes contain potassium and can contribute to hyperkalemia.

Diuretics, which are routinely used by patients with heart failure, may lead to a loss of potassium by the normal kidney which may result low levels of potassium in the blood, termed hypokalemia. Some patients with heart failure receive potassium supplements that are often prescribed routinely along with diuretics. However, if kidney function is poor, an excess intake of potassium supplements may cause hyperkalemia.

Drugs are a very common cause of hyperkalemia through diverse mechanisms. These include drugs frequently used for heart failure and hypertension: e.g. angiotensin converting enzyme inhibitors, angiotensin receptor antagonists, neprilysin inhibitors, aldosterone blockers also called MRAs, β-blockers, digoxin, potassium sparing diuretics (triamterene), the blood thinning drug heparin, and the frequently used over the counter pain killer non-steroidal anti-inflammatory drugs (NSAIDS).

Hyperkalemia may develop intermittently in the presence of known predisposing factors such as chronic kidney disease and heart failure, especially when receiving some of the medications mentioned above. Therefore, patients with heart failure on treatment need to have their blood potassium checked on a regular basis. This is usually done together with kidney function checks, since worsening kidney function is one of the most common causes of hyperkalemia.

What are the consequences of hyperkalemia?

When it develops, mild to moderate hyperkalemia up to 6.5 mmol/liter may cause no symptoms and no immediate problems, but it is associated with a high risk of developing serious heart rhythm disturbances. Severe hyperkalemia (> 6.5 mmol/liter) is a life-threatening medical emergency, requiring immediate attention and medical management. The consequences of hyperkalemia are also affected by other factors such as the presence of heart disease or other blood electrolyte (calcium, magnesium) abnormalities that can increase the risk of heart arrhythmias.

Hyperkalemia can be prevented by frequent monitoring of blood levels, avoiding of potassium rich foods and appropriate dosing of drugs that may lead to hyperkalemia. Often this may mean the use of low doses or stopping certain medication or not stopping. Referral to a dietician may be beneficial in helping to adapt diet in the individual patient.

Hyperkalemia is manageable and reversible directly lowering serum potassium. The type of intervention is determined by the severity of hyperkalemia and associated complications. Acute management for severe hyperkalemia is implemented in the hospital to monitor for complications and includes intravenous therapy and interventions to quickly reduce potassium levels. Occasionally, the rapid removal of potassium from the blood through hemodialysis is required. This is usually only required in patients with severely reduced or absent kidney function.

Long-term interventions include taking way risk factors for hyperkalemia and the administration of therapies that facilitate the removal of potassium from the body. These include dietary potassium restriction and stopping potassium supplements. However, these interventions may not be effective enough to prevent hyperkalemia in patients with heart failure and poor kidney function.

Stopping hyperkalemia-inducing medications that are not essential, such as pain killers, is essential. Several heart failure drug classes may increase the risk of hyperkalemia. This is especially relevant for patients with heart failure and chronic kidney disease who are most prone to developing hyperkalemia.

In patients with heart failure who develop hyperkalemia and need continuous, optimal use of their medications, potassium binding resins, by effectively increasing gastrointestinal elimination of potassium, may be considered. These agents, taken as a powder with water, are well-tolerated and effective at maintaining long-term normal potassium in patients predisposed to hyperkalemia. Importantly, they enable continued optimal use of beneficial heart failure medications.

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ESC Guidelines for Heart Failure

What patients need to know

This guide for patients from the European Society of Cardiology aims to provide an overview of the latest evidence-based recommendations for the diagnosis and treatment of heart failure.

In particular, it should help patients to understand the:

  • main types of heart failure
  • medicines used to treat heart failure
  • devices that may be appropriate
  • importance of rehabilitation
  • management by a multidisciplinary team
  • importance of self-care in managing your own condition

Learn more


A series of 9 simple, captivating animations explaining heart failure and its treatment.

These narrated animations explain how a healthy heart works, what happens to it in heart failure and how various treatments work to improve your health.


In this section you can watch, listen or read interviews with other people with heart failure and their caregivers.


and share your own views and experiences with other patients, families and caregivers.

heartfailurematters.org is a European Society of Cardiology website

The heartfailurematters.org website was developed under the direction of the Heart Failure Association of the European Society of Cardiology (ESC). The ESC is a world leader in the discovery and dissemination of best practices in cardiovascular medicine. Our members and decision-makers are healthcare professionals who volunteer their time and expertise to represent professionals in the field of cardiology in Europe and beyond.

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