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Hyperkalemia (High Level of Potassium in the Blood)


James L. Lewis III

, MD, Brookwood Baptist Health and Saint Vincent’s Ascension Health, Birmingham

Last full review/revision Sep 2021| Content last modified Oct 2021
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In hyperkalemia, the level of potassium in blood is too high.

  • A high potassium level has many causes, including kidney disorders, drugs that affect kidney function, and consumption of too much supplemental potassium.

  • Usually, hyperkalemia must be severe before it causes symptoms, mainly abnormal heart rhythms.

  • Doctors usually detect hyperkalemia when blood tests or electrocardiography is done for other reasons.

  • Treatment includes reducing consumption of potassium, stopping drugs that may cause hyperkalemia, and using drugs to increase potassium excretion.

Causes of Hyperkalemia

Usually, hyperkalemia results from several simultaneous problems, including the following:

  • Kidney disorders that prevent the kidneys from excreting enough potassium

  • Drugs that prevent the kidneys from excreting normal amounts of potassium (a common cause of mild hyperkalemia)

  • A diet high in potassium

  • Treatments that contain potassium

The most common cause of mild hyperkalemia is

  • The use of drugs that decrease blood flow to the kidneys or prevent the kidneys from excreting normal amounts of potassium

Hyperkalemia can develop after a large amount of potassium is released from the cells. The rapid movement of potassium from cells into blood can overwhelm the kidneys and result in life-threatening hyperkalemia.

By itself, increased intake of potassium does not often cause hyperkalemia because normal kidneys do a good job in excreting any extra potassium.


Symptoms of Hyperkalemia

Diagnosis of Hyperkalemia

Treatment of Hyperkalemia

  • Drugs to increase potassium excretion

The disorder that is causing hyperkalemia is treated.

Mild hyperkalemia

For mild hyperkalemia, reducing consumption of potassium or stopping drugs that prevent the kidneys from excreting potassium may be all that is needed. If the kidneys are functioning, a diuretic that increases potassium excretion may be given.

If needed, a resin that absorbs potassium from the digestive tract and passes out of the body in the stool can be given by mouth or enema. Sodium polystyrene sulfonate is a potassium-absorbing resin that is effective but used only for short periods because it can cause excess sodium Hypernatremia (High Level of Sodium in the Blood) In hypernatremia, the level of sodium in blood is too high. Hypernatremia involves dehydration, which can have many causes, including not drinking enough fluids, diarrhea, kidney dysfunction... read more to be retained. Patiromer is a resin drug that can be used for longer periods. It is useful for people who require drugs that usually raise potassium levels, such as angiotensin-converting enzyme (ACE) inhibitors for treatment of heart or kidney disease. Sodium zirconium cyclosilicate also binds to potassium in the gastrointestinal tract. It decreases serum potassium over several hours.

Moderate to severe hyperkalemia

For moderate to severe hyperkalemia, the potassium level must be reduced immediately. Doctors monitor the heart continuously during treatment. Calcium is given intravenously to protect the heart, but calcium does not lower the potassium level. Then insulin and glucose are given, which move potassium from blood into cells, thus lowering the potassium level in blood. Albuterol (used mainly to treat asthma) may be given to help lower the potassium level. It is inhaled.

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