Hyperparathyroidism is an excess of parathyroid hormone in the bloodstream due to overactivity of one or more of the body's four parathyroid glands. These glands are about the size of a grain of rice and are located in your neck.

The parathyroid glands produce parathyroid hormone, which helps maintain an appropriate balance of calcium in the bloodstream and in tissues that depend on calcium for proper functioning.

Two types of hyperparathyroidism exist. In primary hyperparathyroidism, an enlargement of one or more of the parathyroid glands causes overproduction of the hormone, resulting in high levels of calcium in the blood (hypercalcemia), which can cause a variety of health problems. Surgery is the most common treatment for primary hyperparathyroidism.

Secondary hyperparathyroidism occurs as a result of another disease that initially causes low levels of calcium in the body and over time, increased parathyroid hormone levels occur.

Symptoms Causes Risk factors Complications

Hyperparathyroidism is often diagnosed before signs or symptoms of the disorder are apparent. When symptoms do occur, they're the result of damage or dysfunction in other organs or tissues due to high calcium levels circulating in the blood and urine or too little calcium in bones.

Symptoms may be so mild and nonspecific that they don't seem at all related to parathyroid function, or they may be severe. The range of signs and symptoms include:

  • Fragile bones that easily fracture (osteoporosis)
  • Kidney stones
  • Excessive urination
  • Abdominal pain
  • Tiring easily or weakness
  • Depression or forgetfulness
  • Bone and joint pain
  • Frequent complaints of illness with no apparent cause
  • Nausea, vomiting or loss of appetite

When to see a doctor

See your doctor if you have any signs or symptoms of hyperparathyroidism. These symptoms could be caused by any number of disorders, including some with serious complications. It's important to get a prompt, accurate diagnosis and appropriate treatment.

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