What Is Hypercalcemia?

Table of Contents
View All
Table of Contents

Hypercalcemia, an elevated calcium level in the blood, is a serious situation. It can cause vague effects, such as a loss of appetite and fatigue. But if severe or acute, hypercalcemia can affect your muscles and heart rate. High blood calcium is not common, but it can develop due to illnesses like ocancer.

Your calcium level can be measured with a simple blood test, and excess calcium can be managed with procedures that lower calcium levels.

Health screening

Hypercalcemia Symptoms

Many of the symptoms of hypercalcemia are ones that are characteristic of other conditions. Sudden elevations in calcium levels are generally more dangerous than chronic hypercalcemia. Additionally, mildly elevated calcium produces different effects than severely elevated calcium.

Calcium is an essential mineral that helps your muscles contract. If you have excessive calcium, your muscles may twitch or cramp. Even more importantly, your heart muscle can be affected by excess calcium.

Acute hypercalcemia can cause:

Mild Cases
  • Nausea

  • Vomiting

  • Loss of appetite

  • Abdominal pain

  • Constipation

  • Fatigue

Severe Cases
  • Increased thirst

  • Dehydration

  • Decreased urination

  • Muscle cramping, twitching, or weakness

  • Irregular heart rate

Symptoms of chronic hypercalcemia (usually mild) include:

It's especially important for those with kidney disease or cancer to be familiar with the symptoms of hypercalcemia. However, know that symptoms can be hard to recognize and the condition can strike without warning.


Severe hypercalcemia is a major risk to your health. The effects on your heart and nervous system can cause confusion, hallucinations, behavioral changes, and even coma or death.

These issues are rare because the body is generally pretty good at rapidly adjusting variations in calcium concentration. But if you have an issue like cancer, your body might not be able to correct the problem.


There are several causes of high calcium, and the most common ones relate to bone breakdown, cancers, and thyroid concerns.

Causes of hypercalcemia include:

  • Blood cell cancers: Lymphoma and leukemia can both interfere with bone formation and break down bones, releasing excess calcium into the blood.
  • Hyperparathyroidism: The four parathyroid glands, located adjacent to the thyroid gland in your neck, make parathyroid hormone (PTH). This hormone acts on the kidneys to prevent too much calcium from being excreted. High PTH results in hypercalcemia. You can develop high PTH due to a parathyroid overactivity or a parathyroid tumor.
  • Metastatic cancer: Cancer that spreads to the bone (such as breast cancer and prostate cancer) causes the bone to break down, releasing calcium into the blood.

Can Eating Too Much Dairy Cause Hypercalcemia?

No—not if you are healthy, that is. Your thyroid gland makes a hormone, calcitonin, that keeps your blood calcium level from getting too high.


Generally, hypercalcemia is detected based on a blood test. If you have hypercalcemia, there is certainly a medical cause for it. Your medical team may order some other tests to help identify what that is.

Blood and Urine Tests

You can expect that some if not all of these tests will be run as part of the diagnostic process:

  • Complete blood count (CBC): This test can help identify changes that correspond to lymphoma or leukemia
  • Serum electrolytes: You may have other electrolyte abnormalities, such as alterations in sodium, potassium, magnesium, or phosphorous (also regulated by PTH). This test can help your healthcare provider identify a parathyroid or kidney problem.
  • Parathyroid level: Your parathyroid hormone can be detected by a blood test.

Imaging Tests

Imaging may be required when select diagnoses are suspected. This may include:

  • Parathyroid imaging test: If there is a concern about your parathyroid glands, you may need to have an imaging test that visualizes these glands.
  • Bone scan: Because cancer can metastasize to the bone, a bone scan can help identify metastatic lesions.


A bone marrow biopsy or lymph node biopsy can help your medical team with the diagnosis of lymphoma or leukemia.

Even if you are diagnosed with hypercalcemia and don't have signs of heart irregularities, you will probably need an electrocardiogram (EKG) so your healthcare provider can monitor your heart rhythm before you develop any problems. You may also need to have your levels monitored on a regular basis to prevent the unwanted and dangerous effects of the condition.


The treatment of hypercalcemia varies depending upon how elevated your calcium is, as well as the cause. Medical approaches used to decrease one's blood calcium level include medications and interventions.

Management of the primary problem that caused hypercalcemia is an important part of your treatment as well.

Strategies for treating hypercalcemia include:

  • Staying hydrated, particularly if you have a condition that predisposes you to hypercalcemia
  • Intravenous (IV) fluids can help treat dehydration caused by hypercalcemia

Medications used to treat hypercalcemia include:

  • Bisphosphonates, which decrease bone breakdown
  • Calcimar (calcitonin), a medication that can lower elevated calcium levels
  • Gallium nitrate, used to treat cancer-related hypercalcemia
  • Sensipar (cinacalcet), which lowers calcium in the blood
  • Steroids: These drugs may be used in some situations, although steroids can also lower calcium in some instances. The cause of your hypercalcemia will dictate whether steroids are advised or not.

If your hypercalcemia is very severe, you may need dialysis—a process by which your blood is filtered with a machine to eliminate waste material.

A Word From Verywell

Hypercalcemia is rare because the body generally does a good job of maintaining control of calcium concentration. However, illnesses can make it difficult for your body to keep up with excess amounts of the mineral.

If you are prone to hypercalcemia, it is a good idea to meet with a dietitian, stay hydrated, and have your calcium level checked regularly.

2 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Feldenzer KL, Sarno J.Hypercalcemia of Malignancy.J Adv Pract Oncol. 2018 Jul-Aug;9(5):496-504. Epub 2018 Jul 1.

  2. Merck Manuals. Hypercalcemia.

Additional Reading

By Lynne Eldridge, MD
 Lynne Eldrige, MD, is a lung cancer physician, patient advocate, and award-winning author of "Avoiding Cancer One Day at a Time."