Hypercalcemia in Cats: Causes, Symptoms, and Treatment Recognizing and Managing Hypercalcemia in Cats

Hypercalcemia in Cats: Causes, Symptoms, and Treatment https://cdn.pixabay.com/photo/2018/02/02/03/47/cute-3124571_1280.jpg

High blood calcium levels in cats are a symptom of the disorder known as hypercalcemia, which can result from several underlying medical issues. The causes, symptoms, diagnosis, and treatment of hypercalcemia will be examined in this article.

Cats suffer from a condition known as hypercalcemia when their blood calcium levels go over normal. Numerous underlying conditions, such as renal illness, cancer, or thyroid issues, might contribute to the development of high ionized calcium in cats. Hypercalcemia can have detrimental effects on cats' health, including kidney, bone, and other organ damage.

This article will review the causes, signs, treatment, and management of high calcium in cats.


Several underlying disorders can result in feline hypercalcemia, including:

  • Hyperparathyroidism: Hyperparathyroidism, a condition in which the parathyroid gland produces excessive parathyroid hormone (PTH), is the most common cause of hypercalcemia in cats. This hormone controls the amount of calcium in the blood, and when it is overproduced, cats' blood calcium levels are elevated.

  • Cancer: Some malignancies, including lymphoma, leukemia, and multiple myeloma, can result in hypercalcemia. This is because calcium is released from the bones as a result of a chemical called parathyroid hormone-related protein (PTHrP) being produced.

  • Chronic kidney disease: Cats with chronic renal illness may experience hypercalcemia as a result of alterations in their calcium and phosphorus metabolism.

  • Vitamin D Toxicity: Excessive vitamin D supplement use or the use of some rodenticides can cause vitamin D poisoning, which can result in hypercalcemia.

  • Addison's disease: Addison's disease, a condition in which the adrenal glands produce insufficient cortisol and aldosterone, can lead to hypercalcemia.

  • Hypoadrenocorticism: Hypercalcemia can result from the disease known as hypoadrenocorticism, in which the adrenal glands fail to generate enough cortisol and aldosterone.

  • Dehydration: Dehydration can cause a little rise in blood calcium levels.

  • Medication: Some drugs, including thiazide diuretics, might raise the blood's calcium level.


Depending on the underlying cause of the disorder, high calcium in cats can present with a variety of symptoms. Cats may occasionally exhibit no symptoms at all while other times, they may exhibit a variety of symptoms. High calcium levels in cats symptoms include:

  • Increased urination and thirst

  • Diarrhea and gagging

  • Reduced appetite

  • Weakness and sluggishness

  • Dehydration

  • Loss of weight

  • Constipation

  • Higher heart rate

  • A shift in behavior, such as hostility or confusion

  • Breaks and discomfort in the bones


A set of tests are used to diagnose hypercalcemia in cats, which can assist to establish the underlying cause of the problem. These tests may involve the following:


  • Blood Testing: Blood tests can detect calcium levels in the cat's blood, as well as phosphorus, creatinine, and blood urea nitrogen (BUN). These tests can assist determine if there is a calcium imbalance and can also indicate how effectively the kidneys are performing.

  • Urine testing: Urine tests can be used to examine the cat's kidney function and offer further information on the cat's calcium levels.

  • Imaging tests: The cat's organs, bones, or soft tissues may be examined with X-rays, ultrasounds, or CT scans to check for any anomalies that might be the cause of the hypercalcemia.

  • Biopsy: A biopsy of a tumor or organ may be required in some circumstances to diagnose the underlying cause of hypercalcemia.

  • Ionized calcium test: Ionized calcium test for cats is a more definitive test that helps to measure the true level of active calcium in cats.

  • To rule out other potential causes of hypercalcemia, such as hyperthyroidism or vitamin D toxicity, additional testing could be necessary.

How To Treat High Calcium in Cats

The underlying cause of the problem will determine how to treat cats with hypercalcemia. The problem might not always be severe enough to need medical attention. Treatment, however, can be required if the illness is severe or if it is leading to other health issues.

  • Fluid therapy: Giving fluids intravenously to cats can help reduce their blood calcium levels.

  • Medication: Medication can aid in lowering calcium levels. Examples include bisphosphonates and calcitonin.

  • Reducing calcium in cats’ food: Changing the cat's food to one that is low in calcium may assist in lowering the blood calcium levels.

  • Treatment of the underlying problem: If an underlying ailment, such as cancer or renal disease, is the cause of hypercalcemia, treating that condition may assist in reducing calcium levels. Pain relief may be prescribed to help manage pain in the case of cancer. Also, medications such as Furosemide, Salix, and Kidney support capsules may be used to treat underlying kidney conditions.

Prevention Tips

The underlying cause of feline hypercalcemia must be identified to prevent it. Sometimes it might not be possible to stop hypercalcemia. However, there are additional situations when cat owners can take actions to lessen the risk of hypercalcemia, such as:

  • Balanced Diet: Feeding cats a balanced diet may assist in lowering their chance of developing hypercalcemia because it is low in calcium.

  • Routine Check-ups: Checkups with a veterinarian regularly might assist in spotting any health issues before they worsen.

  • Drug monitoring: Some drugs, such as vitamin D supplements, might raise the risk of hypercalcemia. Hypercalcemia risk can be reduced by keeping track of medication usage and talking to a veterinarian about possible adverse effects.

Taking the precautions above can help lessen our feline companions’ risk of getting hypercalcemia.

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