Hyperkalemia

What Is Hyperkalemia? Symptoms, Causes, Diagnosis, Treatment, and Prevention

Cathy Cassata
By Medically Reviewed by 
Reviewed:
Medically Reviewed

Hyperkalemia is a medical term for having too much potassium in your blood.

We all need potassium in our bodies for our nerve and muscle cells, including our heart, to function properly. But high levels of potassium can be life-threatening and require immediate medical care, according to the Mayo Clinic.

Here’s what you need to know about hyperkalemia, including signs, causes, treatments, and more.

Signs and Symptoms of Hyperkalemia

Hyperkalemia usually isn't discovered based on symptoms, which are typically mild and develop gradually over weeks to months.

High potassium levels tend to be found after doctors order routine blood tests for a physical or to diagnose or monitor another condition, notes the National Kidney Foundation.

If you do notice hyperkalemia symptoms, they may include:

  • Nausea
  • Vomiting
  • Weakness
  • Muscle fatigue or weakness
  • Tingling or numbness
If hyperkalemia comes on suddenly or is severe, MedlinePlus says that you may experience the following symptoms that require immediate medical attention:

Sudden or severe hyperkalemia can be life-threatening, so be sure to call your doctor or 911 immediately if you think you have hyperkalemia and especially if you experience the above symptoms.

Causes and Risk Factors of Hyperkalemia

Hyperkalemia occurs when your kidneys can no longer properly remove enough potassium from your blood, causing a buildup of the mineral in the bloodstream.

Hyperkalemia is often linked to one of the following kidney conditions:

Chronic Kidney Disease The loss of kidney function over time, or chronic kidney disease, is the most common cause of hyperkalemia. As the disease advances, your kidneys become less efficient at removing electrolytes (including potassium) from your blood, which then build up in your body, according to the American Kidney Fund.

Acute Kidney Failure When your kidneys suddenly stop filtering your blood due to acute kidney failure, it can lead to the accumulation of dangerous levels of waste products, including potassium.

Other symptoms of acute kidney failure include decreased urine output and swelling in the legs, ankles, or feet, per the Mayo Clinic.

The following conditions have also been linked to hyperkalemia:

Several other factors can contribute to hyperkalemia, including:

How Is Hyperkalemia Diagnosed?

To diagnose hyperkalemia, your doctor will run blood tests to measure your potassium levels as well as an electrocardiogram to check your heart, since heart problems are the most serious complication of hyperkalemia.

A normal blood potassium level is 3.5 to 5.0 millimoles per liter (mmol/L). While normal potassium levels can vary slightly by lab, hyperkalemia is when your blood potassium level is higher than 5.5 mmol/L.

Because it’s common not to experience any hyperkalemia symptoms, your doctor may find high potassium blood levels during another routine blood test.

Otherwise, your doctor may test for hyperkalemia if you have symptoms of or are at risk for the condition (for example, if you take certain medications or have a history of kidney disease).

Your doctor may run additional tests, including blood tests and a urinalysis, to check for other conditions like kidney disease.

Prognosis of Hyperkalemia

The majority of people who are diagnosed with hyperkalemia have an excellent prognosis, as long as the condition is caught early on and treated promptly, notes StatPearls.

Most people with hyperkalemia don’t have complications. Often diet changes are enough to keep potassium levels under control.

Your doctor may order more frequent blood tests to keep an eye on your potassium levels.

Duration of Hyperkalemia

Acute cases of hyperkalemia last just a few days and are manageable with short-term treatment, according to the American Association of Kidney Patients.


For mild hyperkalemia, diet changes are usually enough to normalize potassium levels. In more severe cases, you may require emergency medical treatments, and the condition may occur again.

Chronic hyperkalemia needs to be managed with long-term treatments to keep potassium levels in check.

Treatment and Medication Options for Hyperkalemia

The goal of hyperkalemia treatments is to remove excess potassium from your bloodstream and keep your potassium levels in a normal range. The treatment you’ll receive varies depending on the underlying cause and severity of hyperkalemia.

Your doctor may recommend staying away from salt substitutes and going on a low-potassium diet. Ask exactly how much potassium you’ll need to aim for, since the amount varies from person to person.

Your practitioner may also suggest changing certain medications that could affect your potassium levels.

You might also need to take medications to lower your potassium levels. These include:

  • Diuretics Also know as water pills, these cause your kidneys to create more urine to flush out excess potassium.
  • Potassium Binders This medication binds to potassium and keep it from building up in the bloodstream. You’ll either swallow it as a powder mixed with water or take it as an enema (via the rectum).
If your potassium levels are extremely high, you may need emergency intravenous (IV) therapy, including an infusion of calcium, to protect your heart, and insulin, to move potassium from your bloodstream back into your cells.

You may additionally receive an asthma medication (albuterol) to lower your potassium levels, notes the Cleveland Clinic.

Prevention of Hyperkalemia

If you’re at risk for hyperkalemia, following a low-potassium diet can help lower your odds of being diagnosed with the condition.

Your doctor may recommend limiting or cutting out certain foods from your diet, including:

  • Asparagus
  • Cooked spinach
  • Potatoes
  • Winter squash, including pumpkin
  • Tomatoes and tomato products (like ketchup and sauces)
  • Avocados
  • Bananas
  • Citrus fruits and juices (such as oranges and grapefruit)
  • Dried fruits (such as raisins)
  • Melons (like honeydew and cantaloupe)
  • Nectarines
  • Kiwis
  • Salt substitutes, which contain potassium

Complications of Hyperkalemia

High potassium levels can impact the way your heart works, which can lead to heart arrhythmias and, sometimes, a potentially fatal heart attack.

In addition to the symptoms of hyperkalemia, it’s important to be aware of the symptoms of heart attack, which include:

  • A sensation of squeezing, pressure, or pain in your arms or chest
  • Shortness of breath
  • Breaking into a cold sweat
  • Suddenly feeling dizzy
  • Nausea
  • Stomach pain

Research and Statistics: Who Has Hyperkalemia?

Hyperkalemia affects about 5 percent of the population worldwide and is more common in men than women, possibly due to men’s higher muscle mass.

About 10 percent of all hospitalized people are diagnosed with hyperkalemia, usually due to medications they’re taking or to kidney problems.

Up to 50 percent of all premature babies are also diagnosed with hyperkalemia.

Related Conditions and Causes of Hyperkalemia

Other conditions linked to high potassium levels include:

  • Heart failure
  • Diabetes
  • Peripheral vascular disease
  • Addison's disease
  • AUD (alcoholism)
  • HIV

Resources We Love

National Kidney Foundation

Most hyperkalemia cases are linked to kidney problems. The National Kidney Foundation has loads of helpful information about how your kidneys function as well as tips to prevent kidney disease and manage potassium levels.

American Kidney Foundation

In addition to information about kidney disease and kidney failure, this nonprofit organization’s website offers advice on how to become an advocate for kidney patients and take action on kidney-related issues.

Additional reporting by Colleen De Bellefonds.

Editorial Sources and Fact-Checking


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