Parathyroid hormone (PTH) is primarily used in medical settings to diagnose and manage disorders related to calcium metabolism. It plays a critical role in regulating calcium and phosphate levels in the blood. One of its key applications is in the treatment of hypoparathyroidism, a condition where the body produces insufficient PTH, leading to low calcium levels. In such cases, synthetic PTH analogs, like teriparatide, are administered to restore normal calcium balance and prevent complications like muscle cramps, seizures, and bone abnormalities.

Additionally, PTH is utilized in the management of osteoporosis, particularly in postmenopausal women at high risk of fractures. Teriparatide, a recombinant form of PTH, stimulates bone formation by increasing osteoblast activity, thereby improving bone density and reducing fracture risk. It is often prescribed when other osteoporosis treatments are ineffective or unsuitable.

In diagnostic settings, PTH levels are measured to assess parathyroid gland function and identify conditions such as hyperparathyroidism or hypoparathyroidism. This helps in determining the underlying cause of abnormal calcium levels and guiding appropriate treatment strategies. Overall, PTH and its analogs are essential tools in both therapeutic and diagnostic applications for calcium-related disorders.