To better understand hyperparathyroidism, it helps to understand the anatomy of the parathyroid glands.

The four parathyroid glands are located in the neck, embedded inside of the thyroid gland. These glands are responsible for secreting parathyroid hormone.

Parathyroid hormone regulates calcium, phosphate, and magnesium levels in the body. Increased levels of parathyroid hormone (PTH) cause an increase in blood calcium levels by removing calcium from the bones. The removal of calcium from the bones causes weakness of the bones.