Overview
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In plain language
Parathyroid hormone (PTH) is a natural hormone of 84 amino acids made by four small glands in the neck. It is the body's main controller of blood calcium.
When calcium drops, PTH pulls calcium from bone, helps the kidneys keep it and activates vitamin D. Surprisingly, small daily doses build bone instead of breaking it down, which is why PTH-based medicines treat osteoporosis. Some PTH products have come and gone, so availability needs checking with a clinician.
For students
PTH(1–84) (about 9,425 Da) is secreted by parathyroid chief cells, which sense calcium through the calcium-sensing receptor. Most biological activity lies in the first 34 residues, which bind the PTH1 receptor (PTH1R) in bone and kidney.
In the kidney, PTH increases calcium reabsorption, decreases phosphate reabsorption and stimulates 1-alpha-hydroxylase to make active vitamin D. In bone, continuously high PTH increases resorption, while intermittent exposure stimulates osteoblasts more than osteoclasts: the "anabolic window."
For researchers and instructors
Therapeutics. Teriparatide (PTH 1–34) and abaloparatide (a PTHrP analogue) treat osteoporosis. Full-length PTH(1–84) was approved for hypoparathyroidism but was discontinued; palopegteriparatide, a long-acting PTH(1–34) prodrug, was approved in 2024 for hypoparathyroidism.
Pathology. Primary hyperparathyroidism (usually a benign adenoma) is a common cause of high calcium.
Status. Approved forms exist; check current product availability.
Molecular identity
- Amino acids
- 84
- Molecular weight
- ~9,424.7 Da
- Formula
- C₄₀₈H₆₇₄N₁₂₆O₁₂₆S₂
- Sequence
- Full-length human PTH(1–84)
Origin and history
In 1925 James Collip, the same chemist who helped purify insulin, made the first active extract of parathyroid hormone. Its full sequence was worked out in the 1970s.
It holds a famous paradox: constant high PTH breaks down bone, but short daily pulses build it. That discovery led to teriparatide. A long-acting PTH, palopegteriparatide (Yorvipath), was approved in 2024 for low parathyroid function.
Key people
- James B. CollipFirst active extract (1925)
- John Potts Jr.Led sequencing work
Timeline
- 1925
First active extract
- 1970s
Amino acid sequence determined
- 2002
Teriparatide approved
- 2024
Yorvipath approved for hypoparathyroidism
See every peptide on one history timeline.
Human evidence
Recombinant PTH(1–84) was approved for hypoparathyroidism (Natpara), but its U.S. supply ended in 2024. A long-acting PTH(1–34) prodrug (palopegteriparatide, Yorvipath) was approved in 2024.
Registration and enrollment are not proof of benefit; check study results directly.
Explore original publications and distinguish preclinical findings from controlled human evidence.
Safety and regulatory status
See every compound on the regulatory tracker.
Check current product availability with a clinician.
This profile is educational and does not provide treatment, dosing or sourcing guidance.
Sources
- PubMed literature search: Parathyroid hormone (PTH)
- PubChem compound search: Parathyroid hormone (PTH)
- DailyMed (FDA label search): Parathyroid hormone (PTH)
- PubMed: Collip 1925 parathyroid
- ClinicalTrials.gov search: Parathyroid hormone (PTH)
Hernandez Gener, E. (2026, November 7). Parathyroid hormone (PTH): molecular data, research history and evidence. VALREXA Biosciences. https://valrexa.com/peptides/parathyroid-hormone-pth.html
APA style · Last reviewed November 7, 2026 · Our editorial standardsLast reviewed November 7, 2026. Trial and regulatory status can change; confirm in the linked registries. This profile is educational and is not medical advice, a treatment recommendation, or dosing or sourcing guidance. Report an error · Corrections policy