The term hypercalcemia refers to having too much calcium in the blood. The possible causes include an overactive parathyroid gland, too much vitamin D, some medications, and certain underlying health conditions, such as cancer.
Calcium plays an essential role in the body. It helps build strong bones and teeth while also supporting the muscles, nerves, and heart. However, too much calcium can lead to problems.
In this article, we explore the symptoms, causes, and complications of hypercalcemia. We also describe how doctors diagnose and treat hypercalcemia.
The parathyroid glands are responsible for controlling calcium levels in the blood. These four tiny glands
When the body needs calcium, the parathyroid glands secrete a hormone. This hormone signals:
- the bones to release calcium into the blood
- the kidneys to excrete less calcium into the urine
- the kidneys to activate vitamin D, which helps the digestive tract absorb more calcium
Overactive parathyroid glands or an underlying health condition can disrupt the balance of calcium.
If calcium levels become too high, a person may receive a diagnosis of hypercalcemia. This condition can impede bodily functions and may
Extremely high levels of calcium in the blood can become life threatening.
Mild hypercalcemia may not produce any symptoms, but more serious hypercalcemia can
- Excessive thirst and frequent urination: An excess of calcium forces the kidneys to work harder. As a result, a person may urinate more often, leading to dehydration and increased thirst.
- Stomach pain and digestive problems: Too much calcium can cause an upset stomach, abdominal pain, nausea, vomiting, and constipation.
- Bone pain and muscle weakness: Hypercalcemia can cause the bones to release too much calcium, leaving them deficient. This abnormal bone activity can lead to pain and muscle weakness.
- Confusion, lethargy, and fatigue: Too much calcium in the blood can affect the brain, causing these symptoms.
- Anxiety and depression: Hypercalcemia may also affect mental health.
- High blood pressure and abnormal heart rhythms: High levels of calcium can increase blood pressure and lead to electrical abnormalities that change the heart’s rhythm, adding strain.
Various underlying conditions and other factors can cause hypercalcemia. These include:
Overactive parathyroid glands
The parathyroid glands control calcium levels. If they work too hard, this can lead to hypercalcemia.
The parathyroid glands may become overactive when one becomes enlarged or develops a noncancerous growth.
Hyperparathyroidism is the term for having overactive parathyroid glands. It may be the
Doctors usually diagnose hyperparathyroidism in people aged
Too much vitamin D
Vitamin D triggers calcium absorption in the gut, allowing this nutrient to enter the bloodstream.
The body usually only absorbs
The Office of Dietary Supplements defines a high dosage of vitamin D as
Some types of cancer may cause hypercalcemia. Cancers that commonly lead to this condition include:
In 2021, researchers estimated that hypercalcemia affects
If cancer spreads to the bone, the risk of hypercalcemia increases.
Other health conditions
Other conditions that may cause high blood levels of calcium include:
- thyroid disease
- chronic kidney disease
- adrenal gland disease
- severe fungal infections
People who go for an extended period without being able to move around
People who are severely dehydrated have less water in their blood, which can increase the concentration of calcium. However, this imbalance is usually treatable once a person rehydrates sufficiently.
Some medications can overstimulate the parathyroid gland, and this can lead to hypercalcemia. One example is lithium, which people sometimes take to treat bipolar disorder.
Without proper treatment, hypercalcemia can contribute to several health conditions.
Over time, the bones may release excessive amounts of calcium into the bloodstream, which makes them thinner, or less dense. The continued release of calcium can lead to osteoporosis.
People with osteoporosis have an
- significant disability
- loss of independence
- prolonged immobility
- a curvature of the spine
- becoming shorter over time
People with hypercalcemia are at risk of developing calcium crystals in their kidneys. These crystals can become kidney stones, which are often very painful. They can also lead to kidney damage.
Over time, severe hypercalcemia
An irregular heartbeat
The heart beats when electrical impulses move through it and cause it to contract. Calcium plays a role in regulating this process, and too much calcium
Anyone experiencing symptoms of hypercalcemia should speak with a doctor, who will order a blood test and make a diagnosis based on the results.
A person with mild hypercalcemia may have no symptoms, and doctors might only diagnose the condition after carrying out a routine blood test.
The test will check the blood levels of calcium and parathyroid hormone. The results can show how well some of the body’s systems — such as those involving the blood and kidneys — are functioning.
After diagnosing hypercalcemia, a doctor may perform further tests, such as:
- an electrocardiogram (EKG) to record the electrical activity of the heart
- a chest X-ray to check for lung cancer or infections
- a mammogram to check for breast cancer
- a CT or MRI scan to examine the body’s structure and organs
- dual-energy X-ray absorptiometry, commonly known as a DEXA scan, to measure bone density
People with mild hypercalcemia
If calcium levels continue to rise or do not improve on their own, doctors may recommend further testing.
For people with more severe hypercalcemia, it is important to discover the cause. The doctor may also offer treatments to help lower calcium levels and prevent complications. Possible treatments include intravenous fluids and medications such as calcitonin or bisphosphonates.
If hypercalcemia is due to overactive parathyroid glands, too much vitamin D, or another health condition, the doctor will also treat the condition responsible.
A person with a noncancerous growth on a parathyroid gland may require surgery to remove it.
Certain lifestyle adjustments can help keep calcium levels balanced and bones healthy. These include:
- Drinking plenty of water: Staying hydrated may lower blood calcium levels, and it can help prevent kidney stones.
- Quitting smoking, if applicable: Smoking can increase bone loss. In addition to improving the health of the bones, quitting will reduce the risk of cancer and other health problems.
- Exercising, including strength training: Resistance training promotes bone strength and health.
- Following guidelines for medications and supplements: Following medical advice may decrease the risk of consuming too much vitamin D and developing hypercalcemia.
The outlook for people with hypercalcemia depends on its cause and severity.
Mild hypercalcemia may not require treatment. However, if the condition is more serious, a doctor may prescribe medications that lower the levels of calcium and treat the underlying cause.
Anyone experiencing symptoms of hypercalcemia should speak with a doctor.
Hypercalcemia refers to elevated levels of calcium in the blood. Doctors may discover these increased levels when testing for other conditions.
The possible causes of hypercalcemia include an overactive parathyroid gland, certain medications, too much vitamin D, and underlying health conditions, such as cancer.
The treatment options for hypercalcemia will depend on its severity and cause.