Parathyroid Hormone

Parathyroid hormone regulates calcium levels in the blood, largely by increasing the levels when they are too low. It does this through its actions on the kidneys, bones and intestine. Hyperparathyroidism is the most frequent cause of hypercalcemia in ambulatory patients. Hypoparathyroidism low circulating concentrations of parathyroid hormone (PTH) resulting in low calcium levels and increased phosphate levels in the blood.