Read on for more information about symptoms and diagnosis. This guide also explains what causes hypercalcemia and how to treat it.
Key facts about hypercalcemia
- Hypercalcemia occurs when there is an unusually high calcium level in the blood.
- Primary hyperparathyroidism and malignancy are common causes of hypercalcemia.
- Blood tests can tell you how high or low your blood levels of calcium are.
- Hypercalcemia typically occurs when your blood calcium level is around 12 milligrams per deciliter (mg/dl) or higher.
Read the full article for more information about hypercalcemia.

When there are unusually high levels of calcium in your blood, this is known as hypercalcemia. Because your body needs a certain amount of calcium to function properly, this can affect various organs and bodily systems.
Hypercalcemia can affect the functions of your:
- nerves
- muscles
- digestive tract
- kidneys
- heart
Measurements for blood calcium levels are in mg/dl. Typical blood calcium levels for adults are around 8.5–10.3 mg/dl. Hypercalcemia typically occurs when your blood calcium level is around 12 mg/dl or higher.
The opposite of hypercalcemia is hypocalcemia. This occurs when the calcium level in your blood is too low. Learn more here.
Hypercalcemia occurs when the body cannot regulate and eliminate calcium properly. Two main causes of hypercalcemia are primary hyperparathyroidism and malignancy, or cancer. They account for 90% of hypercalcemia cases.
- Primary hyperparathyroidism causes one or more enlarged parathyroid glands to release excess parathyroid hormone. This can affect the systems that control how much calcium is in the blood. Learn more here.
- If cancer has spread to the bones, this can result in the release of calcium. This may occur due to renal carcinomas, leukemia, lymphoma, rhabdomyosarcoma, multiple myeloma, lung cancer, or breast cancer. Around 30% of people with cancerous cells or cancer experience hypercalcemia.
Other causes of hypercalcemia include:
- hypervitaminosis D, or vitamin D toxicity
- excessive milk intake
- granulomatous conditions, such as:
- endocrine conditions, such as:
- thyrotoxicosis
- hypoadrenalism
- pheochromocytomas
- Williams syndrome
- hypophosphatasia
- hypervitaminosis A
- milk-alkali syndrome
- subcutaneous fat necrosis
- acute or chronic renal failure
- using thiazide diuretics or lithium
Clinicians typically identify the symptoms of hypercalcemia using the mnemonic “groans, bones, stones, moans, thrones, and psychic overtones.” These symptoms and related conditions are as follows:
- groans:
- gastrointestinal symptoms, such as pain, nausea, and vomiting
- peptic ulcer disease
- pancreatitis
- bones:
- bone pain
- osteoporosis
- osteomalacia
- arthritis
- pathological fractures
- stones:
- painful renal stones
- moans:
- fatigue
- malaise, or a general feeling of being unwell
- thrones:
- polyuria, or excessive urination
- polydipsia, or excessive thirst
- constipation
- psychic overtones:
- lethargy
- confusion
- memory loss
- depression
Contact your doctor if you experience any of these symptoms or have any of these conditions alongside symptoms of hypercalcemia.
If your blood calcium level is over 15 mg/dl, even if you are asymptomatic, you will require treatment for hypercalcemia. The type of treatment you receive can depend on how much calcium is in your blood, what symptoms you experience, and whether or not you have any other medical conditions.
Your doctor may advise that you do not take anything that can encourage increased calcium levels. This can include:
- calcium supplements
- lithium mood stabilizers
- water tablets or diuretics
- certain medications for heartburn or acid reflux
Other treatments for hypercalcemia are as follows.
Fluid intake to flush out calcium
You may receive fluid through a drip to flush out the extra calcium. Your doctor may also encourage you to drink more water to help this process.
Medications to reduce calcium levels
Steroids taken either orally or by injection can help reduce calcium levels. Your doctor may also recommend bisphosphonates or calcitonin to lower high levels of calcium.
Some medications, such as
bisphosphonates, also help strengthen bones. These are particularly useful if hypercalcemia occurs due to cancer.
Surgery to remove parathyroid glands
If hypercalcemia occurs due to hyperparathyroidism, you may require surgery to remove the source of the parathyroid hormone that is responsible for the excess calcium.
Your doctor will assess you to see if you present the common symptoms of hypercalcemia. This can involve using the mnemonic “groans, bones, stones, moans, thrones, and psychic overtones” to see if your symptoms match those commonly present in cases of hypercalcemia.
If your doctor suspects hypercalcemia, they will arrange for you to have a calcium blood test. This is a straightforward blood test wherein they will draw blood from a vein in your arm or hand. They will then test it to see if your calcium levels are too high, too low, or within a typical range.
If hypercalcemia occurs as a side effect of cancer, it is not possible to prevent it.
If it occurs due to a diet rich in calcium or the use of calcium supplements, reducing your calcium intake can reduce your risk of future hypercalcemia.
Contact your doctor before making any major changes to your diet.
If you do not receive treatment for hypercalcemia, this could result in complications. These can include:
- bone pain
- constipation
- depression
- kidney stones
- pancreatitis
- renal failure
- gastric ulcers
- paresthesias
- syncope and arrhythmias
Contact your doctor as soon as you suspect that you might have hypercalcemia. Receiving prompt treatment may help reduce the risk of complications.
Having a diet rich in calcium can lead to high levels of calcium in your blood. It is important to be aware of how much calcium you need.
See the table below for the recommended dietary allowance of calcium by age group and sex.
Age | Male | Female |
---|---|---|
0–6 months* | 200 mg | 200 mg |
7–12 months* | 260 mg | 260 mg |
1–3 years | 700 mg | 700 mg |
4–8 years | 1,000 mg | 1,000 mg |
9–13 years | 1,300 mg | 1,300 mg |
14–18 years | 1,300 mg | 1,300 mg |
19–50 years | 1,000 mg | 1,000 mg |
51–70 years | 1,000 mg | 1,200 mg |
70+ years | 1,200 mg | 1,200 mg |
* adequate intake
If needed, to reduce your intake of calcium, avoid large servings of dairy items and foods that are calcium-fortified. These include:
- calcium-fortified cereals
- calcium-fortified orange juice
- milk
- cheese
- cottage cheese
- yogurt
- ice cream
Learn more about the health benefits of calcium and how to monitor your intake here.
Contact a doctor as soon as you experience any symptoms of hypercalcemia. If you have a condition that can cause hypercalcemia, make your doctor aware of this when you explain your symptoms.
Below are some other frequently asked questions about hypercalcemia. Dr. Megan Soliman, M.D., has provided the answers.
How do you fix hypercalcemia?
The first thing to do is remove the underlying cause, if possible. This would include cases of too much calcium intake, too much vitamin D supplementation, and other causes. If calcium levels remain high after this, or if they are high due to another condition (such as malignancy), IV hydration should be started.
This may be all that is required in people with mild to moderate hypercalcemia. However, individuals with severe hypercalcemia and those with moderate hypercalcemia that is not improving may need medications such as calcitonin, bisphosphonates, IV loop diuretics, and steroids.
What is a dangerously high calcium level?
In general, a level above 14 mg/dl is considered severe and requires urgent treatment. However, some people may be more sensitive to lower levels — such as 12–13 mg/dl — and still develop symptoms and require aggressive treatment as well.
Should I take vitamin D if I have hypercalcemia?
It depends on the cause of your hypercalcemia. If it is due to high vitamin D supplementation, or intoxication, any further vitamin D supplementation should be avoided.
However, if someone has high calcium levels due to another cause — such as hyperparathyroidism — and has results that show a vitamin D deficiency, they can safely take vitamin D supplements. This should be with no calcium supplementation and with close physician monitoring.
What happens if hypercalcemia is left untreated?
Without treatment, hypercalcemia can lead to severe complications, including kidney failure and cardiac arrest. It is crucial for anyone who has symptoms of hypercalcemia to contact a doctor and arrange an evaluation promptly.
Hypercalcemia refers to unusually high levels of calcium in the blood. This typically occurs due to primary hyperparathyroidism or malignancy, but it can also happen as a result of other conditions.
Examples of hypercalcemia symptoms include gastrointestinal pain, bone pain, fatigue, and excessive urination. If you have hypercalcemia, you will likely be able to treat it with fluids and medications to reduce your calcium levels. In some cases, you may require surgery.
Contact your doctor if you have symptoms of hypercalcemia. They will arrange for a blood test to check how high your calcium levels are.