Hypocalcemia happens when the level of calcium in your blood (not your bones) is too low. Several different health conditions can cause hypocalcemia. The symptoms of hypocalcemia depend on how mild or severe it is. It is treatable and can last for a short time or be chronic depending on the cause.
Hypocalcemia is a treatable condition that happens when the levels of calcium in your blood are too low.
Many different health conditions can cause hypocalcemia, and it’s often caused by abnormal levels of parathyroid hormone (PTH) or vitamin D in your body. Hypocalcemia can be mild or severe and temporary or chronic (lifelong).
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Calcium is one of the most important and common minerals in your body. Most of your body’s calcium is stored in your bones, but calcium is needed in your blood as well.
The calcium in your blood helps your nerves work, helps make your muscles squeeze together so you can move, helps your blood clot if you are bleeding and helps your heart work properly. A low level of calcium in your blood (hypocalcemia) can hinder your body’s ability to perform these important functions. You also need calcium in your bones to make them strong.
If you don’t consume enough calcium in your diet, your body takes calcium from your bones to use in your blood, which can weaken your bones. Hypocalcemia happens when there are low levels of calcium in your blood, not your bones.
The levels of calcium in your blood and bones are controlled by two hormones called parathyroid hormone and calcitonin. Vitamin D also plays an important role in maintaining calcium levels because it’s needed for your body to absorb calcium.
Hypocalcemia can affect people of all ages, including infants. The age at which someone could develop hypocalcemia usually depends on the cause. For example, if an infant has hypocalcemia, it’s often because of a genetic disorder.
Healthcare professionals and researchers have not yet determined how common hypocalcemia is. This is likely because hypocalcemia is usually a side effect of other health issues.
Hypocalcemia is a common side effect of having your thyroid removed (thyroidectomy). Approximately 7% to 49% of people have temporary hypocalcemia after thyroidectomy.
People who have mild hypocalcemia often have no symptoms (are asymptomatic). The symptoms of hypocalcemia depend on if it’s mild or severe.
Symptoms of mild hypocalcemia can include:
If left untreated, over time hypocalcemia can cause neurologic (affecting the nervous system) or psychologic (affecting the mind) symptoms, including:
Severe hypocalcemia (very low levels of calcium in your blood) can cause the following symptoms:
There are many complex functions and factors involved with maintaining a steady level of calcium in your blood and body. Because of this, several different health conditions and disorders can cause hypocalcemia.
Most of the time, an issue with your parathyroid hormone (PTH) levels and/or vitamin D level(s) is involved with the cause of hypocalcemia. This is because PTH helps control the level of calcium in your blood and vitamin D helps your body absorb calcium.
The three most common causes of hypocalcemia include:
Other causes of hypocalcemia include:
You have hypocalcemia if your total serum (blood) calcium concentration is less than 8.8 mg/dL. Your healthcare provider may find mild hypocalcemia incidentally (by chance) from routine blood tests or by testing for other conditions.
Healthcare providers use a calcium concentration blood test to diagnose hypocalcemia. Figuring out and diagnosing the cause of hypocalcemia is just as important as diagnosing the hypocalcemia itself.
Your healthcare provider may perform the following tests or procedures to try to determine the cause of your hypocalcemia or to be sure your hypocalcemia isn’t affecting other parts of your body:
Oral calcium supplements are the most common treatment for hypocalcemia. Treating the cause of hypocalcemia is just as important as treating the hypocalcemia itself. If you’re taking a medication that is causing your hypocalcemia, your healthcare provider may change it or adjust it in order to return your calcium levels to normal.
The following treatments and medications are often used for hypocalcemia:
Risk factors for developing hypocalcemia can include having:
Unfortunately, there’s nothing you can do to prevent hypocalcemia. Although it may seem that eating and drinking more calcium could prevent hypocalcemia, a lack of calcium in your diet usually doesn’t affect the amount of calcium in your blood. Maintaining adequate calcium intake, however, is important for bone health.
Hypocalcemia is a treatable condition. Symptoms of hypocalcemia usually go away once your calcium levels are back to normal. If left untreated, severe hypocalcemia can cause life-threatening complications such as seizures and congestive heart failure. Be sure to contact your healthcare provider if you’re experiencing symptoms and go to the nearest hospital if you are experiencing severe symptoms.
Depending on the cause, you could have temporary or chronic (lifelong) hypocalcemia. Ask your healthcare provider how long you can expect to have hypocalcemia and how long you’ll have to take medication.
Hypocalcemia can be potentially life-threatening if it’s not diagnosed and treated in time. Be sure to contact your healthcare provider if you’re experiencing symptoms.
Be sure to contact your healthcare provider if you’re experiencing symptoms of hypocalcemia. If you have chronic hypocalcemia, it’s important to see your healthcare provider regularly so that you can be sure your calcium levels are healthy and that your treatment is working.
If you’ve been diagnosed with hypocalcemia, it may be helpful to ask your healthcare provider the following questions:
A note from Cleveland Clinic
Getting a diagnosis can be scary. Know that hypocalcemia is treatable and that symptoms usually go away once your calcium levels are back to normal with treatment. Don’t be afraid to ask your healthcare team questions about your hypocalcemia and its management.
Last reviewed by a Cleveland Clinic medical professional on 05/31/2022.
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