What is hyperparathyroidism?

Hyperparathyroidism is a condition in which one or more of your parathyroid glands become overactive and release (secrete) too much parathyroid hormone (PTH). This causes the levels of calcium in your blood to rise, a condition known as ++hypercalcemia++.

What are the parathyroid glands?

Your parathyroid glands secrete PTH to help control the levels of calcium and phosphorous in your body. You have four parathyroid glands, located on the outside borders on the backside of your thyroid gland. Your thyroid gland is located on the front of your neck.

What happens when there’s too much parathyroid hormone (PTH) circulating in my body?

If you have an overactive parathyroid, one or more of your parathyroid glands makes too much parathyroid hormone (PTH). Too much PTH signals your body to make more calcium available. Your body responds by:

  • Releasing more calcium into your blood from your bones (where most of your calcium is stored). Loss of calcium from your bones weakens them and increases your risk of a fracture.
  • Having your digestive tract absorb more calcium from the foods you eat.
  • Having your kidneys retain calcium and return it to your blood instead of flushing it out in your urine. Too much calcium in your kidneys can cause kidney stones to form.

Who gets hyperparathyroidism?

Approximately 100,000 people develop hyperparathyroidism in the United States every year. Older women who are postmenopausal are at the highest risk for the condition.

How does hyperparathyroidism occur?

There are two types of hyperparathyroidism, primary and secondary:

  • In primary hyperparathyroidism, your parathyroid glands make too much PTH, which causes the level of calcium in your blood to rise.
  • In secondary hyperparathyroidism, the overactivity of the parathyroid glands occurs in response to another condition that’s causing calcium loss. Parathyroid overactivity is an attempt on your body’s part to keep the calcium levels normal. Examples of conditions that lower calcium levels include ++kidney failure++, severe ++vitamin D deficiency++ and severe calcium deficiency.

Causes of primary hyperparathyroidism include:

  • A noncancerous (benign) growth, called an adenoma, forms on a single parathyroid gland. The adenoma causes the gland to overact and make more PTH. This is the most common cause.
  • Two or more of your parathyroid glands become enlarged, a condition called hyperplasia, and produce too much hormone.
  • Radiation treatment to the neck area.
  • Inherited conditions, such as multiple endocrine neoplasia type 1. This is a rare cause.
  • Cancer of a parathyroid gland (rare).

What are the symptoms of hyperparathyroidism?

If you have early hyperparathyroidism, you may not have any symptoms. If you have mild hyperparathyroidism, you may have some of the following symptoms:

  • Joint pain.
  • Muscle weakness.
  • Feeling tired.
  • Depression.
  • Trouble concentrating.
  • Loss of appetite.

If your hyperparathyroidism is more severe, you may have these symptoms:

  • Nausea and vomiting.
  • Confusion, forgetfulness.
  • Increased thirst and need to urinate.
  • Constipation.
  • Bone pain.

Other problems associated with severe hyperparathyroidism include:

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