Comprehensive Guide to Hypercalcemia

In contrast to a calcium deficiency, hypercalcemia or hypercalcemia has an increased calcium level in the blood. In order to avoid more far-reaching disorders, it is advisable to consult a doctor for further diagnosis and treatment.

What is hypercalcemia?

Symptoms are absent in half of all patients with hypercalcemia. The phenomenon is often only discovered by chance during a blood test. See AbbreviationFinder for abbreviations related to Hypercalcemia.

Hypercalcemia is defined as too high a level of calcium in the blood. Values ​​of more than 2.7 mmol/l in humans for the total calcium in the bloodstream are considered decisive here. In the case of ionized (free) calcium, a value of more than 1.3 mmol/l is referred to as hypercalcemia.

There is talk of a real calcemic crisis when the total value has risen above 3.5 mmol/l. Then there is polyuria (greatly increased urine output), vomiting, dehydration, fever and psychoses. Ultimately, a coma can result.


Calcium metabolism disorders can have many causes: The most common causes are malignant tumours, mostly bronchial carcinomas, breast cancer and what is known as multiple myeloma, a cancer of the bone marrow.

In second place would be osteolytic hypercalcemia. This is particularly the case with bone metastases and plasmacytomas. The cancer cells release substances that increase the calcium metabolism.

Third, there is paraneoplastic hypercalcemia. It is caused by peptides that are similar to parathyroid hormone. These peptides are produced by tumors. Approximately 90% of all patients with this form of hypercalcemia have such peptides in their blood, whether bone metastases exist or not. In dogs, hypercalcemia occurs most commonly in anal gland tumors.

Another cause is hyperparathyroidism, which affects about 20% of hypercalcemia patients. Adrenal insufficiency (Addison’s disease), hyperthyroidism (overactive thyroid gland) and multiple endocrine neoplasia (MEN) are also possible causes.

Symptoms of intoxication continue the series of factors from which hypercalcemia could result. These include, above all, poisoning with vitamins, in other words, excessive doses of certain vitamins, especially vitamins A, D and D3.

It should be noted that unnecessarily high levels of these vitamins are found in both ready-to-eat and supplementary foods for dogs and cats. In humans, an overdose is therefore rather rare.

Intoxications caused by tamoxifen and certain diuretics can also be responsible, at least temporarily, for an excessively high blood calcium level. Furthermore, an increased intake of lithium, calcium-containing ion exchangers, teriparatide and theophylline. Immobilization also leads to hypercalcemia, which means resting certain parts of the body (leg in a cast) or bed rest.

Other causes that do not weigh very heavily in percentage terms:

  • Sarcoidosis (these are nodules of tissue, usually in the lungs).
  • Hypercalcemia secondary to kidney transplantation. Here, temporary renal insufficiency may have caused the parathyroid gland to overfunction.
  • Also, an overdose of calcium, for example through high consumption of dairy products or too high intake of supplements.
  • Hereditary hypercalcaemia due to poor calcium excretion by the kidneys.
  • Acromegaly (a growth disorder caused by overproduction of growth hormone).
  • Pheochromocytoma (a growth of the adrenal gland, which can be malignant or benign).
  • Hypophosphatasia (an extremely rare inherited disorder of bone metabolism).

Symptoms, Ailments & Signs

The symptoms of hypercalcemia depend on the level of calcium concentration in the blood. In most cases, non-specific symptoms occur that also occur in other diseases. As a result, hypercalcemia is often only discovered incidentally during an examination. If there is only a slight excess of calcium, there are often no symptoms at all.

Otherwise, the disease is characterized by a variety of different complaints that can affect the heart, kidneys, digestive system, nervous system and muscles. This can lead to cardiac arrhythmia. Furthermore, the body often reacts with nausea, vomiting, constipation and loss of appetite. Kidney stones and calcium salts can build up in the kidneys.

The kidney stones can either remain silent or lead to renal colic. Furthermore, there is often an increased excretion of urine with a simultaneous strong feeling of thirst. When the muscles are involved, muscle weakness develops with a decrease in general performance. When the nervous system is affected, drowsiness and impaired consciousness often occur.

Furthermore, the development of a so-called organic brain syndrome with behavioral problems, memory disorders, anxiety, lack of interest and exhaustion is possible. When the calcium level exceeds 3.5 millimoles of calcium per liter of blood, a life-threatening hypercalcemic crisis occurs.

The hypercalcemic crisis develops within a few days and, in addition to nausea and vomiting, is also characterized by severe cardiac arrhythmia, fever, dehydration, increased fluid loss due to polyuria and disturbances of consciousness up to coma. Hypercalcemic crisis leads to death in 50 percent of cases.

Diagnosis & History

Symptoms are absent in half of all patients with hypercalcemia. The phenomenon is often only discovered by chance during a blood test. Otherwise, the symptoms of the underlying disease appear as well as increased water excretion, nausea, constipation, vomiting, sometimes pancreatitis, cardiac arrhythmias, listlessness, muscle weakness, extreme sleepiness, psychosis and coma.

The diagnosis is made primarily via a laboratory blood test and the search for causal parameters, eg tumors, as well as an examination of the parathyroid hormone, calcitriol and PTHrP levels.


Due to the excess of calcium in the body, the patient can experience various ailments and complications. In order to avoid long-term damage, a doctor should always be consulted. In most cases, no clear diagnosis can be made for a relatively long time, since the hypercalcemia does not show any clear symptoms and signs.

Frequent urination usually occurs and the sufferer suffers from vomiting and nausea. In some cases, it can lead to heart problems, so that the person concerned is no longer resilient and usually feels exhausted and listless. There is also a general feeling of illness and weakness.

The muscles are also weak and can no longer be used in the usual way. Constipation is not uncommon. The symptoms can thus extremely limit and complicate the everyday life of the patient. The treatment of hypercalcemia always depends on the causes of the disease. As a rule, acute emergencies can also be treated with the help of solutions and infusions. There are no further complications.

When should you go to the doctor?

Hypercalcemia does not always produce clear symptoms. A doctor should be consulted if increased water excretion is noticed. Frequent urination is often associated with nausea and vomiting, constipation and fatigue. If these symptoms appear, medical advice is needed. At the latest when signs of cardiac arrhythmia or muscle weakness are noticed, the complaints must be taken to the family doctor.

If the excess calcium is not treated, it can lead to a circulatory collapse or even a heart attack. Therefore, a doctor should be consulted early on, who can clarify the symptoms and treat them if necessary before serious complications arise. In the event of a circulatory collapse or other medical emergency, an ambulance must be called. The affected person requires immediate medical treatment and must then be treated in hospital. In the case of hypercalcemia, a general practitioner or internist is usually consulted. If the bones are involved, an orthopedist must also be consulted . The initial diagnosis can be made by the general practitioner.

Treatment & Therapy

Therapy attempts to eliminate the causes. For example, by surgical removal of a tumor. Otherwise, you will try to stop calcium intake from food as much as possible.

Acute symptom control can be achieved by administering a physiological saline solution and furosemide and simultaneously initiating water excretion.

If tumors are present, bisphosphonates may be given to limit osteoclast function. In addition, the administration of glucocorticoids can be helpful because they work against vitamin D. If you have kidney failure, dialysis is also an option. The hormone calcitonin can be administered as an emergency measure to lower the calcium level very quickly.

Outlook & Forecast

In the case of hypercalcemia, the prospect of a cure depends on the causal trigger of the oversupply of calcium in the organism. In severe cases, there is a tumor disease. If this can be successfully removed and no metastases form in the body, there is a chance that the hypercalcemia will be cured. If an aggressive tumor is diagnosed that cannot be adequately treated, the hypercalcemia will be present until the end of the patient’s life. In these cases, serious symptoms of the person concerned are treated, but no attempt is made to cure side effects.

In less dramatic cases, a clear alleviation of the symptoms and a cure can already be achieved by changing the diet. With a balanced and healthy food supply, there is a continuous breakdown of the excess calcium until complete normalization occurs. Permanent healing is possible if the diet that has been worked out is also used in the long term.

In acute health conditions, an infusion can reduce the calcium level. However, this is not a permanent measure that results in freedom from complaints. Only a removal of the current calcium content in the organism takes place. If the cause is not treated, the nutrient will then be regenerated and the symptoms will immediately recur.


Hypercalcemia can only be prevented to a limited extent, as it can accompany several other diseases. One possibility is to largely avoid the intake of calcium and vitamin D3 with food. However, this should only be done after consulting a doctor, since these substances are also vital.


In most cases, those affected with hypercalcemia do not have any special follow-up measures available. First and foremost, the disease must be recognized and treated correctly and, above all, at an early stage by a doctor, so that there are no further complications and no further deterioration of the symptoms.

In most cases, dietary intake can be controlled, requiring the sufferer to adjust their diet properly. The doctor can also help and create a nutrition plan for the person concerned. The person affected should also drink plenty of water to eliminate excess calcium. After successful treatment, care must be taken not to trigger hypercalcemia again.

The reason for the hypercalcemia should also be identified so that the disease cannot recur. In severe cases or in the case of severe poisoning, medication can also be taken to lower the calcium level. If treated quickly, the hypercalcaemia does not reduce the life expectancy of the affected person.

You can do that yourself

Hypercalcemia can have very different causes and is not diagnosed by the patient himself. It usually comes to light during the examination of blood values, which takes place as part of another diagnosis. First and foremost, it is important to find out what causes the hypercalcemia in order to be able to choose a correct and appropriate form of therapy. The patient cannot contribute too much to this, but he can speed up the process by being willing to cooperate and answering questions precisely.

The patient contributes to his recovery by trusting and following the therapy plan and the advice of his doctor. If deviations occur, he should report these to the doctor as soon as possible, as well as any other peculiarities that he notices.

Parallel to the therapy, the patient can support his recovery by as healthy and stable a lifestyle as possible. Sufficient sleep and occasional rest breaks during the day support balance and a good general condition. Reducing obesity and adapting eating habits to a healthy and balanced diet also make a major contribution to improving health. Provided that the overall condition allows it, a moderate sports and exercise program is also very beneficial for the condition and the cardiovascular system. Basically, the better the general condition, the better the chances of recovery.


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