What Is PTH 1-34? Benefits, Research & Safety
The biologically active fragment of parathyroid hormone approved for osteoporosis treatment, representing the first anabolic bone therapy.
UK summary: UK prescription-only medicine (Forsteo / teriparatide). First-line anabolic osteoporosis therapy for severe disease or where anti-resorptive therapy has failed. Time-limited course (typically 2 years).
Quick Facts
Overview
PTH 1-34 — evidence and risk at a glance
Twenty standard modules scored against the Peptide Authority evidence grading methodology. Missing modules indicate the field has not yet been characterised editorially — treat absences as uncertainty rather than reassurance.
01Evidence snapshot
UK prescription-only medicine (Forsteo / teriparatide). First-line anabolic osteoporosis therapy for severe disease or where anti-resorptive therapy has failed. Time-limited course (typically 2 years).
02Human evidence grade
03Preclinical evidence grade
04Regulatory status
- UK: Approved (Forsteo) for severe osteoporosis.
- EU: Approved for osteoporosis when other treatments unsuitable or failed.
- Notes: Teriparatide is approved in UK, EU, US, and many other countries. Usage criteria vary; often reserved for severe cases or treatment failures. Biosimilars are now available in some markets.
05Approved medical uses
- Severe postmenopausal osteoporosis (Forsteo — MHRA-licensed POM, NICE TA161, max 24 months).
- Osteoporosis in men at high fracture risk.
- Glucocorticoid-induced osteoporosis.
06Unapproved / promotional claims
- General bone-density supplement.
- Sports performance through bone strengthening.
- Replaces bisphosphonates as first-line.
07Common internet claims
- Marketed by some online sources as bodybuilding bone-density boost.
08Claim vs evidence
| Claim | Evidence | Human evidence? | Regulatory concern | Safer wording |
|---|---|---|---|---|
| “Builds bone faster than bisphosphonates” | A | Yes | Low | Teriparatide is anabolic (forms new bone); bisphosphonates are anti-resorptive (slow bone loss). They work differently; teriparatide is generally reserved for severe disease. |
09Safety uncertainty score
Safety profile partly characterised; some signals from observational or preclinical data.
10Known adverse signals
- Transient hypercalcaemia, leg cramps, nausea, orthostatic hypotension.
- Osteosarcoma rodent signal (limits use to 24 months).
- Contraindicated in Paget's, prior radiation, hypercalcaemia, hyperparathyroidism.
11Drug-interaction uncertainty
Some interaction data published; check with a prescriber for your specific medicines.
12Anti-doping status
13UK legal position
Approved (Forsteo) for severe osteoporosis.
14EU legal position
Approved for osteoporosis when other treatments unsuitable or failed.
15What this page cannot tell you
- Whether grey-market 'PTH 1-34' products contain the labelled compound at safe concentration.
- Long-term safety beyond 24 months in any patient population.
16Last reviewed
17Citation quality score
18Research gaps
- Comparative-effectiveness vs romosozumab in head-to-head Phase 3 settings.
19Safer alternatives / established care pathways
- NICE TA161 osteoporosis pathway under endocrinology / rheumatology.
- Bisphosphonate first-line per NICE.
20Doctor discussion prompts
Questions to ask a qualified clinician
These are starter questions you can adapt for a GP, specialist, pharmacist, or anti-doping advisor. The aim is to help you have a better-informed conversation — not to replace one.
- Am I eligible for teriparatide given my osteoporosis severity?
Discovery & History
Mechanism of Action
Researched Benefits
Based on preclinical and clinical research findings:
- 1Significant reduction in vertebral fractures (65-70%)
- 2Reduction in non-vertebral fractures (35-50%)
- 3Substantial increases in bone mineral density
- 4Improved bone architecture and quality
- 5Effective in severe osteoporosis and prior fractures
- 6Can be used when anti-resorptives have failed
Claim vs Evidence
How popular claims about PTH 1-34 stack up against the current research, graded using our public evidence grading methodology.
| Claim | Evidence | Human evidence? | Regulatory concern | Safer wording |
|---|---|---|---|---|
| “Builds bone faster than bisphosphonates” | A | Yes | Low | Teriparatide is anabolic (forms new bone); bisphosphonates are anti-resorptive (slow bone loss). They work differently; teriparatide is generally reserved for severe disease. |
Theoretical Dosing & Protocols
| Theoretical Dosage | 20 mcg subcutaneous injection daily |
| Frequency | Once daily |
| Duration | Up to 24 months (2 years maximum per current labeling) |
| Notes | Teriparatide is a prescription medication for severe osteoporosis. Treatment duration is limited. Should be followed by anti-resorptive therapy to maintain bone gains. Medical supervision and monitoring required. |
Administration Routes
Routes studied in research settings (educational only):
- Subcutaneous injection (daily)
- Pen device for self-administration
| Half-Life | Stability |
|---|---|
| Approximately 1 hour when given subcutaneously | Requires refrigeration; stable per manufacturer specifications |
Safety Profile & Known Risks
Commonly Reported Side Effects
- Nausea
- Headache
- Dizziness
- Leg cramps
- Injection site reactions
- Transient hypercalcemia
Rare Risks & Concerns
- Osteosarcoma (boxed warning based on rat studies; not observed in humans)
- Hypercalcemia requiring dose adjustment
- Orthostatic hypotension (early doses)
Contraindications
- Prior radiation to skeleton
- Bone metastases or history of skeletal malignancy
- Metabolic bone diseases other than osteoporosis
- Pre-existing hypercalcemia
- Pediatric populations with open epiphyses
- Paget's disease
UK & EU Regulatory Context
🇬🇧 United Kingdom
Approved (Forsteo) for severe osteoporosis.
🇪🇺 European Union
Approved for osteoporosis when other treatments unsuitable or failed.
Clinical Studies Summary
Effect of parathyroid hormone (1-34) on fractures and bone mineral density in postmenopausal women with osteoporosis.
Pivotal trial demonstrating significant reduction in vertebral and non-vertebral fractures with teriparatide.
Safety and Efficacy of PTH 1-34 and 1-84 Therapy in Chronic Hypoparathyroidism: A Meta-Analysis of Prospective Trials.
Limitations of the study included considerable population overlap between the reports, incomplete data, and heterogeneity in the protocol design.
Potential effects of teriparatide (PTH (1-34)) on osteoarthritis: a systematic review.
The SR demonstrated that PTH (1-34) could alleviate the progression of OA. Moreover, PTH (1-34) had beneficial effects on osteoporotic OA (OPOA) models, which might be a therapeutic option for OA and OPOA treatment.
Impact of recombinant PTH on management of hypoparathyroidism: a systematic review.
Of 2,141 studies identified, only eleven studies fitted the inclusion criteria. These studies suggest that rPTH is useful in normalising serum calcium levels. Excretion of urinary calcium levels is reduced with PTH 1-34 but remained unchanged in a number of studies using PTH 1-84. Recombinant PTH is well tolerated. The majority of studies included post-surgical hypoparathyroidism with marked heterogeneity.
Parathyroid hormone and its related peptides in bone metabolism.
The action mechanism of these PTH-related peptides is not exactly the same as that of PTH. Thus, the mechanisms of PTH and PTH-related peptides in bone metabolism were reviewed in this paper.
Abaloparatide and the Spine: A Narrative Review.
Abaloparatide (synthetic parathyroid-related peptide (PTHrP), Tymlos, Radius Health, Waltham, MA), the second drug in this family, has recently become available for use. In this narrative review, we review the mechanism, effects, and benefits of abaloparatide compared to alternative treatments as well as discuss the current literature in regard to its effect on osteoporosis-related complications in the spine.
Registered Trials & Regulatory Status
32 of 66 completed trials have never posted results. Unreported trials are not neutral: results that go unpublished are more often negative ones.
To Evaluate the Efficacy and Safety of Abaloparatide Injection (QLG2128) in the Treatment of Postmenopausal Women With Osteoporosis and at High Risk of Fracture
Status: Not Yet Recruiting · 282 participants · Qilu Pharmaceutical Co., Ltd.
Conditions: Postmenopausal Women With Osteoporosis
Post-surgical Outcomes With Anabolic Agent Use in High-risk Ankle Fractures: A Pilot RCT
Status: Not Yet Recruiting · 80 participants · University of Calgary
Conditions: Ankle Fractures
Precision Medicine Approach for Osteoporosis - Follow Up Study
Status: Enrolling By Invitation · 40 participants · Paul F Netzel
Conditions: Osteoporosis
Teriparatide on Maxillary Sinus Floor Osseointegration
Status: Unknown · 42 participants · Universidad de Valparaiso
Conditions: Bone Regeneration
Assess Safety and Compare PK of New Oral hPTH(1-34) Tablet Formulations vs. EBP05 Tablets and Subcutaneous Forteo
Status: Completed · 45 participants · Entera Bio Ltd.
Conditions: Hypoparathyroidism, Osteoporosis, Fractures, Bone
Fracture Recovery for Returning to Duty (Teriparatide STRONG)
Status: Enrolling By Invitation · 183 participants · University of South Carolina
Conditions: Stress Fracture of Tibia or Fibula
Novel Precision Medicine Approach to Treatment of Osteoporosis Based on Bone Turnover
Status: Active Not Recruiting · 60 participants · Madhumathi Rao
Conditions: Age-Related Osteoporosis
Study Evaluating PK of PTH Administered Orally Via RaniPill™ Capsule
Status: Completed · 50 participants · RANI Therapeutics
Conditions: Healthy Volunteers
Treatment of Adynamic Bone Disorder With Parathyroid Hormone in Chronic Kidney Disease
Status: Recruiting · 48 participants · Ditte Hansen
Conditions: Adynamic Bone Disease, Chronic Kidney Diseases, Cardiac Disease
Real-world Effectiveness and Cardiovascular Safety Study of Abaloparatide in Postmenopausal Women
Status: Completed · 22,054 participants · Radius Health, Inc.
Conditions: Osteoporosis, Postmenopausal
Pharmacokinetic and PHarmacodynamic Analysis and Evaluation of Teriparatide (PTH 1-34) Between Sexes
Status: Completed · 30 participants · Norfolk and Norwich University Hospitals NHS Foundation Trust
Conditions: Stress Fracture
Effect of Vitamin K Supplementation on Circulating Levels of Osteocalcin on the Bone Metabolism and Aging
Status: Terminated · 99 participants · University of Milano Bicocca
Conditions: Bone Metabolism Disorder, Aging Disorder, Osteoporosis
Adverse event reports (FDA FAERS)
Not applicable: no licensed product contains this peptide, so it is not reported through FAERS. This is an absence of surveillance, not evidence of safety.
Source: ClinicalTrials.gov and openFDA. Updated automatically.
Looking for PTH 1-34?
Source research-grade PTH 1-34 from a trusted UK supplier — third-party tested with certificate of analysis.
View at SupplierFrequently Asked Questions
Questions to ask a qualified clinician about PTH 1-34
These are starter questions you can adapt for a GP, specialist, pharmacist, or anti-doping advisor. The aim is to help you have a better-informed conversation — not to replace one.
- Am I eligible for teriparatide given my osteoporosis severity?
UK regulatory & safety context
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