Minute-to-minute custody of blood calcium, because the margin between a working nerve and a failing one is narrower than most physiology allows.
Identity
- Class
- Peptide hormone (84 aa)
- Source
- Parathyroid glands
- Receptor
- PTH1 receptor (PTH1R), a class B GPCR
Key properties
Evidence floorClinicalREF1CLIN1Approximate values for the native hormone; engineered analogs are often deliberately larger and far longer-acting. Each figure carries its own provenance tier, and the floor is the weakest of them - the Standard.
Mechanism
Released within minutes of a fall in blood calcium, PTH acts on bone and kidney to raise it — mobilizing calcium from bone, increasing renal reabsorption, and stimulating activation of vitamin D. Its effect on bone is paradoxically dual: continuous exposure is catabolic, but intermittent exposure is anabolic.
Reference notes
- PTH is the body's fastest defense against low blood calcium.
- Intermittent PTH builds bone; continuous PTH breaks it down — a striking pulsatility effect.
- It raises calcium partly by activating vitamin D in the kidney.
Regulatory status
United States · reviewed September 2026- Basis
- Teriparatide (Forteo, PTH 1-34) approved for osteoporosis; palopegteriparatide (Yorvipath) for hypoparathyroidism.
Status describes the molecule as a drug substance under US law and is an editorial reading of the public record — approvals, trial registrations, and the FDA 503A bulk-substances list. It is not legal advice and it changes; the review date above is the last time the table was checked. Other jurisdictions are noted only where they differ materially.
Common questions
- What is Parathyroid hormone (PTH)?
- The fast-acting hormone that raises blood calcium. Structurally it is Peptide hormone (84 aa).
- How does PTH work?
- Released within minutes of a fall in blood calcium, PTH acts on bone and kidney to raise it — mobilizing calcium from bone, increasing renal reabsorption, and stimulating activation of vitamin D. Its effect on bone is paradoxically dual: continuous exposure is catabolic, but intermittent exposure is anabolic.
- How strong is the evidence for PTH?
- PeptideHormone grades PTH at the "Established" evidence tier — its mechanism and core effects are settled across the peer-reviewed literature. It is catalogued as an endogenous signal the body produces itself, and the tier is an editorial judgment about the public literature that can change as the science does.
- What is the half-life of PTH?
- The reported circulating half-life of PTH is ~2–4 min.
- Is PTH FDA-approved?
- Yes — as of September 2026, PTH is an approved prescription medicine in the United States. Teriparatide (Forteo, PTH 1-34) approved for osteoporosis; palopegteriparatide (Yorvipath) for hypoparathyroidism. Status is US-centric and can change; check the FDA record for the current position.
In the literature
Live registry counts · retrieved- Ph 131
- Ph 271
- Ph 356
- Ph 466
Searched as Parathyroid hormone, PTH, teriparatide. Counts are search hits from the primary registries, not a curated set and not a grade – a measure of how much work exists on PTH, not how it turned out.
Selected literature
Curated peer-reviewed reviews, sourced from PubMed. Selected for relevance, not exhaustive — open any entry on PubMed for the full record and its primary citations.
- 1.Parathyroid hormone and its related peptides in bone metabolism · Biochemical pharmacology, 2021 · PMID 34224692
- 2.Parathyroid hormone: past and present · The Journal of endocrinology, 2005 · PMID 16423810
External references
PTH in the public knowledge graph — the same entity resolved across the authoritative chemistry and protein databases.