Hypercalcemia in Cats
Can very easily result in the mineralization of several soft tissues

Hypercalcemia in cats if moderate to severe is a medical emergency as it is adversely affecting several of your cat internal organs.

Especially hard hit will be the kidneys, the heart, the nervous system, as well as the intestinal tract.

If this condition is not immediately addressed, serious damage as well as mineralization of soft tissues can also occur.

If your cat only has a mild case of this condition, they may show absolutely no symptoms at all until it worsens and suddenly explodes in a vicious attack on your cat’s body.


Calcium is the most abundant mineral that is found in your cat with approximately 99% of it found in the bones while the remaining 1% is found in extra cellular fluid.

This is the fluid in your cat that is found outside of the cells and between the cells in the body tissue.

It is essential for several functions in your cat including the strengthening of bones and teeth, cardiac functions, as well as nerve and muscle contractions.

Calcium is stored in your cat’s skeleton and it is released when it is required by the immune system.

However, when something goes wrong with this system, and calcium enters into your cat blood, the result is Hypercalcemia.

Deep blue eyes in catsRat poison can easily trigger Hypercalcemia in cats

Hypercalcemia in cats is a condition where there is an abnormally high concentration of calcium in the blood.

Blood calcium concentrations are measured in milligrams also referred to as mg, per deciliter, or dl. One hundred milliliters equals one deciliter.

The normal measurement of blood calcium concentrations in healthy cats is between 9.0 and 11.5 mg/dl.

Conversely anything above 12.0 mg/dl is considered abnormal and can cause very serious damage in your cat.

There are several symptoms that you can watch for that your cat may be experiencing moderate forms of Hypercalcemia.


The first symptom of Hypercalcemia in cats will be Anorexia; but it will be much more than just a loss of appetite.

In some cases, they may stop eating altogether.

This will than develop into a dehydration in your cat, and as a result they will start to drink huge amounts of water to counter not eating.

As the condition increases in severity, your cat may become constipated, or they will show the exact opposite symptoms including diarrhea as well as vomiting.

A very rapid weight loss will than follow.

There are several potential causes of Hypercalcemia in cats including several diseases or Vitamin D poisoning.

Vitamin D is necessary in promoting calcium in your cat.

However when they get toxic effects from a source containing excessive vitamin D, it unleashes large amounts of Calcium from the skeleton and some of this mineral is absorbed into their blood.


There are three diseases that can cause Hypercalcemia in cats and cause your pet’s calcium levels to rise very rapidly and the first is called Lymphoma.

This is a form of malignant cancer that involves the lymphoid system in your cat.

This system is extremely important in your cats overall immune system as it is a major defense mechanism against attacks by viruses and bacteria.

Lymphoid tissues are found in your cat’s lymph nodes, liver, spleen, the gastrointestinal tract, as well as their skin.

The next potential cause of Hypercalcemia in cats will be from a chronic kidney failure, also referred to as renal disease.

It is considered the most common disease in senior cats but it can also be the result of a bacterial, viral, or fungi infection, as well as a toxicity of some kind.

The final potential disease is Primary Hyperparathyroidism, which is the result of an over active parathyroid gland located in your cats neck.

The result in an excessive secretion of the parathyroid hormone, PTH, which in turn causes elevated calcium levels in your cat’s bloodstream. It is almost always caused by a benign tumor.

The next set of causes is of Hypercalcemia in cats is from Vitamin D toxicity, but it is not from the vitamin itself.

Cats are naturally attracted to rat poison; especially the pellet forms and they are extremely toxic to your cat for two distinctive reasons.

The first is Vitamin K and its actions. Rat poison is designed especially to deplete the Vitamin K in rats so they cannot form blood clots.

Anticoagulants are used in rat poison so they will slowly bleed to death and it is extremely effective; however, it also deploys another attack utilizing Vitamin D in toxic levels.


One of the most potent forms of this vitamin, cholecalciferol, is used in almost every form of rat poison.

It is designed to raise the serum calcium levels in rats to excessive levels, which will kill them.

This also works very well and it can place the health of your cat in severe jeopardy if they ingest it as the calcium is released in mass from the skeleton.

The next form of Vitamin D toxicity is from a common house plant, day blooming Jessamine.

This very popular house plant contains a natural ingredient that has almost the exact same chemical compound as vitamin D and cats are naturally attracted to the smell.

However, the effect on cats is almost the same as rat poison as it releases deadly amounts of calcium by the immune system if ingested.

The final potential cause of Vitamin D toxicity in your cat is from topical ointments, especially those used for psoriasis.

Cats are naturally attracted by the smell but they also have very dangerous results if ingested.

Hypercalcemia in cats can be extremely dangerous to your cat. In some of the cases it is caused by underlying diseases, but in the majority of cases it is caused by Vitamin D toxicity.

If it is severe, your veterinarian will administer Intravenous fluids that will excrete the calcium out in your cat’s urine.


There are also several drugs that can be used to produce the same results if it is not considered life threatening.

However, the best way you can prevent your cat from getting this vicious condition is to keep them away from rat poison.

However also keep them from day blooming Jessamine house plants and all topical creams that you may use, as most of them with contain very high doses of Vitamin D.

Pet Medications for Hypercalcemia in Cats

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