Hyperthyroidism is the most common disease of the Parathyroid Glands. Hyperparathyroidism is the overproduction of the Parathyroid Hormone by one or more of the glands. Hyperparathyroidism results in high levels of calcium in the blood (Hypercalcemia).


Hyperparathyroidism is commonly caused by a Parathyroid Adenoma or enlargement of all of the Parathyroid Glands (Primary Hyperparathyroidism). Primary Hyperparathyroidism usually occurs randomly, but some people inherit a gene that causes the disorder. The most effective treatment of Primary Hyperparathyroidism is surgical removal of the malfunctioning Parathyroid Gland(s). Causes of Primary Hyperparathyroidism include:


Parathyroid Adenoma is a non-cancerous tumor of the Parathyroid Glands. It is the enlargement of one Parathyroid Gland and accounts for about 90 percent of all patients with Primary Hyperparathyroidism. Multiple Parathyroid Adenomas are seen in 5-10 percent of patients with primary Hyperparathyroidism. The enlarged gland(s) produce excessive Parathyroid Hormones resulting in Hyperparathyroidism.


Parathyroid Hyperplasia is the growth and over-activity of all four Parathyroid Glands. It is also referred to as Four Gland Hyperplasia. Parathyroid Hyperplasia accounts for 2-5 percent of patients with Primary Hyperparathyroidism.


Parathyroid Cancer is a rare cause of Primary Hyperparathyroidism. It accounts for less than 1 percent of patients with Primary Hyperparathyroidism.


Hyperparathyroidism can also be a result of another disease that affects the glands’ function (Secondary Hyperparathyroidism). The most common cause of Secondary Hyperparathyroidism is kidney failure. Secondary Hyperparathyroidism is usually managed by treating the underlying medical problem.


Most patients with Hyperparathyroidism have no symptoms. Hyperparathyroidism is often discovered accidentally when blood tests done for another medical reason reveal high calcium levels. Symptoms that may occur include:

  • Osteoporosis
  • Bone fractures
  • Bone pain
  • Muscle weakness
  • Kidney stones
  • High blood pressure
  • Heart palpitations
  • Confusion
  • Depression
  • Memory loss
  • Lethargy
  • Constipation
  • Abdominal pain
  • Peptic ulcer disease
  • Nausea