The parathyroid glands make parathyroid hormone (PTH), a substance that controls the level of calcium in your blood, which is important for the normal functioning of your muscles and nerves. PTH acts on bone cells, the small intestine and the kidneys and causes a rise in the level of calcium in the blood.
There are typically four parathyroid glands, which are normally each the size of a grain of rice. They are usually located near to the thyroid gland, but are sometimes found elsewhere in the neck or behind the breastbone.
What can go wrong with the parathyroid glands?
If one or more parathyroid gland becomes overactive (known as ‘hyperparathyroidism’), too much calcium circulates in the blood. Over time calcium loss from bones leads to the risk of fractures (broken bones) and the high levels of calcium in the blood can damage many organs including blood vessels, the kidneys, stomach, pancreas and possibly the heart.
Hyperparathyroidism is diagnosed with blood tests and a urine test. It may require surgery.
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