Parathyroid Hormone Unit Converter

Parathyroid hormone (PTH) is a polypeptide hormone produced by the four parathyroid glands located behind the thyroid in your neck. It is the primary regulator of calcium levels in your blood.

When blood calcium drops, your parathyroid glands release PTH to restore balance. PTH acts on bones, kidneys, and intestines to increase calcium in the bloodstream. When calcium returns to normal, PTH secretion decreases through a negative feedback loop.

The biologically active form is intact PTH, an 84-amino acid peptide with a short half-life of about 4 minutes. PTH is often measured alongside calcium, phosphate, and vitamin D to fully assess calcium metabolism.

PTH is produced and secreted by the chief cells of the four parathyroid glands, which are small pea-sized glands located on the posterior surface of the thyroid gland in the neck.