Excessive Potassium in the Blood in Cats

Although some potassium is necessary, it is possible for your cat to have too much. This condition is known to veterinarians as hyperkalemia. Several different health problems can cause elevated potassium levels and though treatable, all can cause serious health problems if left unchecked. Your cat may not show any symptoms if his potassium levels are only slightly elevated, but the condition can escalate quickly in the absence of treatment. This makes routine vet visits and blood work extremely important tools for keeping your cat healthy.

Potassium is an essential electrolyte found in the blood of cats as well as humans. In a cat, potassium helps to regulate several body functions, including muscle contractions, nerve impulses and heart function. Without it, the heart, skeleton, blood pressure and muscles are unable to function properly.

If your cat's potassium is only slightly elevated, she may not give you any indication that there is a problem with her health. Unfortunately, symptoms may not appear until your cat is already experiencing distress. When symptoms do appear, they typically include:

• Involuntary muscle twitches and spasms
• Extreme lethargy and lack of energy
• Muscle weakness
• Constipation
• Loss of appetite

Your cat may also experience cardiac arrhythmias, more commonly referred to as an irregular heartbeat, if her potassium levels are high. Though your vet will surely notice this symptom, you are not likely to. Coughing and fainting spells are possible, however, if the arrhythmia is severe.

In cats, the kidneys are responsible for filtering excess potassium from the blood so that it can be excreted through urination. As a result, a high potassium level in cats are almost always caused by problems in the urinary tract. Diabetes, however, can also be to blame. Likely causes of high potassium include:

• Kidney failure
• Urinary tract blockage
• Ruptured bladder (typically associated with traumatic injury)
• Addison's disease

The detection of high potassium levels requires a simple blood test. Your veterinarian will take a blood sample from your cat and send it to a lab to determine exactly how much potassium is present. In cats, a normal potassium level is between 3.4 and 5.6 MEQ/L. Although the exact measurement can vary a bit from one cat to another, levels of 6 to 6.5 MEQ/L or higher typically indicate an excess of calcium in the blood. 

If your cat's potassium levels are high, your veterinarian will want to know why and will begin searching for the underlying cause of the problem. He will likely start by taking note of other numbers on your cat's lab report. Cats with elevated potassium, BUN, and creatinine levels may be experiencing kidney failure.

High levels of potassium may also prompt your vet to perform an ECG (electrocardiogram). This test measures your cat's heart rate and tells your vet if your cat's increased potassium levels have caused an irregular heartbeat. Because potassium levels are often elevated as a result of a blockage in the urinary tract, your vet may also perform an ultrasound to look for blockages.

The treatment plan for high potassium levels depends upon the underlying cause of the problem. Your veterinarian will treat high potassium as a symptom rather than as your cat's main issue and could treat for any of the following:

Kidney failure

Your veterinarian will help you develop a diet for your cat that is low in protein and phosphates. He may also prescribe medication that will bind with the potassium in your cat's body so he can once again excrete it through his urine. Treatment will continue throughout your cat's life to keep him as comfortable and healthy as possible.

Urinary Tract Blockage

If a blockage is present, the vet will remove it using a catheter whenever possible. In cases of severe blockage, surgery may be required to manually remove the block or create a new opening that allows urine to pass.

Ruptured Bladder

Your cat will need surgery to repair her bladder.

Addison's Disease

Because Addison's disease causes a decrease in hormones, treatment requires medication that increases the amount of adrenal hormone in the body. This treatment will need to be maintained throughout the cat's life.

Diabetes

Reducing potassium levels in diabetic patients involves using diet, exercise, and medication to control the cat's blood sugar levels. Like Addison's disease, diabetes requires lifelong monitoring and treatment.

Fluids are often given to hyperkalemic cats regardless of the cause in an attempt to increase their urinary (and therefore, potassium) output.

Cats suffering from a urinary blockage or ruptured bladder should make a full recovery. After surgery, your pet may need less food for a day or two. You'll need to watch the wound for signs of infection as it heals and visit your vet for a post-surgery checkup. Your cat should be back to normal in a week to 10 days, if not sooner.

Diabetes and Addison's disease both require lifelong treatment and management. Medications will keep your cat healthy and happy, but will be required for the rest of the animal's life. With proper treatment, however, your cat can have a long and healthy life with both of these diseases. To manage Addison's disease, your cat will need a daily pill or a monthly shot. The methods used to treat diabetes will vary and may include pills as well as insulin shots. Regular blood monitoring will also be necessary as directed by your vet.

Kidney failure, unfortunately, can not be cured. It can, however, be managed so your cat can maintain an excellent quality of life. When treatment begins, your vet may recommend doing a blood test once a month to monitor potassium levels while adjusting medication dosages. When your cat's potassium level has returned to normal and stayed there for a month or two, testing frequency can be reduced.