Why was sermorelin withdrawn?
The manufacturer discontinued it in 2008 citing manufacturing and commercial reasons; no safety withdrawal occurred.
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Tier 1 — Human RCT (formerly approved)
Sermorelin
Pulsatile GH Secretion & Axis-Preserving Growth Hormone Stimulation
Sermorelin — GHRH(1-29)NH₂ Growth Hormone-Releasing Hormone Analog
Last reviewed: August 2026
Research Purposes Only. Sermorelin is supplied by Purgo Labs strictly for qualified laboratory research use only. It is not intended for human or veterinary use, nor for diagnostic, therapeutic, or cosmetic application. Statements on this page have not been evaluated by the FDA.
CR
Written By
Compound Review Research Team
Reviewed for Scientific Accuracy By
Megan FleuryPharmD, MBA, RP
Reviewed the scientific, mechanism, and research content on this page. This review does not cover dosing protocols or sourcing/vendor information, which are provided separately for research reference only.
Reviewed: August 2026
All content is reviewed for scientific accuracy against peer-reviewed literature. View our editorial methodology.
So What Does This Actually Mean?
Plain English summary — no PhD required
Sermorelin is a shortened version of the hormone your brain uses to tell your pituitary gland to make growth hormone. It's 29 amino acids long — just the active fragment of the full 44-amino-acid signal — and it was FDA-approved for treating growth hormone deficiency in children under the brand name Geref®.
What It Does
Instead of injecting growth hormone directly, sermorelin tells your pituitary gland to make its own. This is a meaningful distinction: when you inject GH directly, your body gets a large, non-pulsatile dose that bypasses its normal feedback systems. Sermorelin works upstream — it rings the doorbell and lets the pituitary decide how much GH to release, which means the body's natural checks and balances stay intact. In research models, this produces a more physiological GH pulse pattern.
Why It Matters
Growth hormone is released in pulses, with the largest pulse occurring shortly after sleep onset. Sermorelin's short half-life (~10–20 minutes) makes it well-suited to amplify this natural sleep pulse when timed appropriately. Researchers studying GH deficiency, body composition, sleep quality, and age-related GH decline have used sermorelin as a tool to study axis-preserving GH stimulation.
The Bottom Line
Sermorelin is one of the most established GHRH analogs in research, with a clinical history in pediatric GH deficiency and a well-characterized safety profile. Its axis-preserving mechanism and short half-life make it a distinct option compared to longer-acting analogs like CJC-1295 DAC or tesamorelin. All research-grade sermorelin from Purgo Labs is for laboratory use only.
Overview
What is Sermorelin?
Sermorelin is a synthetic analog of endogenous growth hormone-releasing hormone (GHRH) comprising the biologically active N-terminal 29 amino acids of the 44-residue native peptide. This truncated fragment retains full receptor-binding activity at the GHRH receptor (GHRHR) on pituitary somatotrophs while offering improved synthetic accessibility and a well-characterized pharmacokinetic profile.
Unlike exogenous growth hormone administration, sermorelin stimulates the pituitary to produce and secrete GH through its own endogenous feedback mechanisms. This axis-preserving mechanism maintains the pulsatile pattern of GH release, preserves hypothalamic-pituitary-axis (HPA) negative feedback, and avoids the supraphysiological GH levels associated with direct GH injection. Sermorelin was previously FDA-approved under the brand name Geref® for the diagnosis and treatment of growth hormone deficiency in children, providing a meaningful clinical safety dataset.
Key Takeaways
- Sermorelin is the biologically active N-terminal 29-amino acid fragment of endogenous GHRH (1-44), binding GHRH receptors on pituitary somatotrophs to stimulate pulsatile GH secretion.
- Unlike direct GH administration, sermorelin preserves the hypothalamic-pituitary feedback axis — somatostatin-mediated inhibitory feedback remains intact, maintaining physiological GH pulse architecture.
- FDA-approved as Geref® (1997) for pediatric growth hormone deficiency; voluntarily withdrawn in 2002 for commercial (not safety) reasons, providing a meaningful clinical safety foundation.
- Short half-life (~10–20 min) makes bedtime administration optimal — amplifies the natural sleep-onset GH pulse rather than creating off-cycle, non-physiological GH elevation.
- Compared to CJC-1295 DAC (half-life ~6–8 days) and tesamorelin (FDA-approved for visceral fat), sermorelin offers the most physiological GH pulse pattern with the longest safety history.
Composition
Molecular Composition
Amino Acid Sequence
YADAIFTNSYRKVLGQLSARKLLQDIMSRQQGESNQER (29 AA)
Sermorelin consists of the first 29 amino acids of the 44-residue human GHRH sequence: Tyr-Ala-Asp-Ala-Ile-Phe-Thr-Asn-Ser-Tyr-Arg-Lys-Val-Leu-Gly-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Met-Ser-Arg (YADAIFTNSYRKVLGQLSARKLLQDIMSRQQGESNQER). The C-terminus is amidated in the acetate salt form (sermorelin acetate), which is the standard research-grade formulation.
With a molecular weight of 3,357.9 Da, sermorelin is substantially smaller than full-length GHRH (5,040 Da) and tesamorelin (5,135.9 Da), making it more cost-effective to synthesize at high purity. The N-terminal tyrosine residue is critical for GHRHR binding; modifications at this position substantially reduce biological activity.
Mechanism of Action
How Does It Work?
!
Sermorelin stimulates pulsatile growth hormone release by mimicking the brain's GHRH signal at the pituitary, preserving the body's natural GH feedback axis.
Sermorelin binds to the GHRH receptor (GHRHR), a Gs-coupled GPCR expressed on anterior pituitary somatotroph cells. Receptor activation stimulates adenylyl cyclase, elevating intracellular cAMP and activating protein kinase A (PKA). PKA phosphorylates downstream targets that promote both GH synthesis (via CREB-mediated transcription of the GH gene) and GH secretion (via calcium-dependent exocytosis of GH-containing secretory granules).
Because sermorelin acts upstream of the pituitary, GH release remains subject to normal somatostatin-mediated inhibition and physiological negative feedback from circulating IGF-1. This preserves the pulsatile, amplitude-modulated pattern of GH secretion that characterizes normal physiology — a key mechanistic distinction from exogenous GH or longer-acting GHRH analogs like CJC-1295 DAC, which can blunt pulsatility through sustained receptor occupancy.
"Sermorelin acetate stimulates the pituitary gland to produce increased amounts of human growth hormone and is the only available GHRH analog that has been clinically evaluated for the treatment of adult growth hormone deficiency." — Walker et al., Journal of Clinical Endocrinology & Metabolism, 1990
Signaling Pathways
Key Research Pathways
GHRHR / cAMP / PKA Signaling
Binds GHRH receptor on pituitary somatotrophs, activating adenylyl cyclase → cAMP → PKA cascade to stimulate GH synthesis and pulsatile secretion.
GH / IGF-1 Axis Activation
Secreted GH drives hepatic IGF-1 production, mediating downstream anabolic effects on muscle, bone, and metabolism.
Somatostatin Feedback Preservation
Unlike direct GH administration, sermorelin's upstream action preserves somatostatin-mediated inhibitory feedback, maintaining physiological GH pulse architecture.
CREB-Mediated GH Gene Transcription
PKA phosphorylates CREB transcription factor, upregulating GH gene expression in somatotroph cells for sustained GH synthesis.
Research Highlights
Key Findings from the Literature
- Previously FDA-approved (Geref®) for GH deficiency diagnosis and treatment in pediatric patients
- Stimulates pulsatile GH release while preserving somatostatin-mediated negative feedback
- Increases serum IGF-1 levels in GH-deficient subjects (Walker et al., 1990)
- Half-life of ~10–20 minutes allows precise dosing windows around sleep-onset GH pulse
- Axis-preserving mechanism avoids pituitary desensitization seen with continuous GHRH exposure
- Studied in adult GH deficiency, body composition, sleep quality, and anti-aging protocols
How Long It Lasts & How It Works in the Body
Sermorelin — half-life, bioavailability, onset, and duration data
Subcutaneous (SC)
| Parameter | Value | Source |
|---|---|---|
| Half-Life (t½) | ~10–20 minutes Very short; requires daily dosing, typically at bedtime | Prescribing Information |
| Time to Peak (Tmax) | ~5–20 minutes Rapid absorption after SC injection | Prescribing Information |
| Bioavailability (F) | Estimated 50–70% (SC) Rapidly degraded by serum proteases | Preclinical Data |
| Onset of Action | Minutes GH pulse begins within minutes of injection | — |
| Duration of Action | 30–60 minutes Short GH pulse; bedtime dosing aligns with natural GH release | — |
Shortest half-life of the GHRH analogs. Bedtime dosing is standard to align with the natural nocturnal GH pulse. Requires daily administration.
References:
• Geref Prescribing Information
• Walker RF. Curr Opin Investig Drugs 2006
Researcher Notes
Important Research Context
Sermorelin's clinical history provides a meaningful safety foundation. The Geref® formulation was used in pediatric growth hormone deficiency for over a decade before market withdrawal (due to commercial, not safety, reasons). Adult research has focused on GH deficiency, body composition, sleep quality, and anti-aging applications. Its short half-life (~10–20 min) requires careful timing — typically administered at bedtime to amplify the natural sleep-onset GH pulse. Compared to CJC-1295 (with DAC), sermorelin's pulsatile action is considered more physiological; compared to tesamorelin, it lacks the visceral fat-reduction clinical dataset but has a longer history of use and lower cost.
Research References
Peer-reviewed literature supporting the research profile of Sermorelin
The following peer-reviewed studies form the primary evidence base for Sermorelin's research profile. All references are sourced from PubMed, NCBI, and peer-reviewed scientific journals. Published research is available through PubMed, NCBI, and peer-reviewed biomedical journals.
- 1.
Walker RF. Sermorelin: a better approach to management of adult-onset growth hormone insufficiency?. Clinical Interventions in Aging. 2006.PMID: 18046908
Sermorelin restores physiological GH pulsatility and is well-tolerated in adult GH insufficiency.
- 2.
Vittone J, et al. Effects of single nightly injections of growth hormone-releasing hormone (GHRH 1-29) in healthy elderly men. Metabolism. 1997.PMID: 9005976
Nightly sermorelin injections increased IGF-1 and improved body composition in elderly men.
- 3.
Corpas E, Harman SM, Blackman MR. Human growth hormone and human aging. Endocrine Reviews. 1993.PMID: 8491152
Established the rationale for GHRH-based therapies in age-related GH decline.
Research Databases
Sermorelin
Growth Research
From $59.99
Purgo Labs list price, read 12 Sep 2026 · per-lot COA on the vendor page
1 vial (10mg)
List price · read 12 Sep 2026
$59.99
Use code HEALTH for 20% off
Where to buy Sermorelin
11 partners · prices read from product pages, latest 1 Nov · ranked by rubric, then price
- 1 certificate verified at the labout of stock 1 Nov10mg$59.99→ $47.99
- 2 certificates verified at the lab5mg$25.00→ $20.00
- 1 certificate verified at the lab10mg$64.30$45.00→ $40.50
Every order also needs bacteriostatic water — add it to the same cart.All Sermorelin vendors, partners and not
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Sourced from Purgo Labs
✅≥99% Purity
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Technical Specifications
- Peptide Class
- GHRH analog — N-terminal 29-residue fragment
- Molecular Weight
- 3,357.9 Da
- Amino Acid Sequence
- YADAIFTNSYRKVLGQLSARKLLQDIMSRQQGESNQER (29 AA)
- Receptor Target
- GHRH receptor (GHRHR) on pituitary somatotrophs
- Half-Life
- ~10–20 minutes (short-acting)
- Available Sizes
- 5mg vials
- Form
- Lyophilized powder
- Purity
- ≥99% (third-party tested)
Known Interactions
7 documented interactions for Sermorelin
CJC-1295Caution
Both are GHRH analogs targeting the same receptor. Combining may cause excessive GH release. Generally use one or the other, not both.
Emerging evidence
MK-677Caution
Both increase GH secretion via different mechanisms. Combining may cause excessive GH/IGF-1 elevation.
Emerging evidence
IpamorelinSynergistic
Both stimulate GH release via complementary pathways. Commonly co-administered in anti-aging protocols.
Emerging evidence
IGF-1 LR3Synergistic
Sermorelin stimulates GH release; IGF-1 LR3 provides direct anabolic signaling. Complementary.
Emerging evidence
Interaction data is based on published research, known pharmacological mechanisms, and clinical practitioner experience. Evidence tiers: Clinical = human data; Emerging = preclinical/case reports; Theoretical = mechanism-based inference. Always consult a qualified healthcare provider before combining compounds.
Source Sermorelin at Purgo Labs
≥99% purity · Third-party COA · Use code HEALTH for 20% off
Vendor Scoreboard — top 3 by verified evidenceVerified 1 November 2026
Related Research
Other Compounds in This Guide
Safety
Sermorelin side effects
Approved-drug dataFormerly approved drug (Geref, 1997–2008) — profile from its label and trials
Sermorelin was an approved diagnostic and paediatric GH-deficiency treatment, so its adverse effects were documented under regulation: injection-site reactions, flushing, headache, dizziness and, less often, hyperactivity or nausea. It was withdrawn for commercial reasons, not safety. The research-grade product is not the former drug.
Research-use information only. Research-grade Sermorelin is not an approved medicine; where trial or label figures appear below they belong to the pharmaceutical product studied, not to any research vial. This section does not give dosing or medical advice.
What is reported
Every rate carries its source. Where no source exists, no rate is printed.
| Effect | Rate (sourced) | Detail | Source |
|---|---|---|---|
| Injection-site reactions (pain, redness, swelling) | not quantified | Most common finding. | Geref label |
| Facial flushing, headache, dizziness | not quantified | Transient, dose-related. | Geref label |
| Hyperactivity, somnolence, nausea | not quantified | Less common. | Geref label |
What is not known
- •Long-term use in adults without GH deficiency — the approved indication was paediatric.
- •Research-grade identity and dose.
Mechanism-based cautions
- •Raises GH/IGF-1; the same theoretical concerns as any secretagogue in people with active malignancy.
- •Interaction with glucocorticoids and thyroid status alters response.
Regulatory status: Approved as Geref (1997); discontinued in 2008 for non-safety reasons. Research-grade sermorelin is not approved.
Side-effect references
- EMD Serono Geref (sermorelin acetate) prescribing information. FDA label, 1997.
What is actually in a research vial
Everything above describes Sermorelin the molecule. The risk specific to a research vial is different: it may not contain Sermorelin at the labelled amount, and it may contain what the synthesis left behind. Identity (mass spectrometry), purity (HPLC), measured net content and an endotoxin result are the four lines on a certificate that bear on adverse effects, and only a certificate you can check at the laboratory tells you any of them. This is what we have verified for Sermorelin so far.
Who sells Sermorelin, and what they document
25 of the 105 vendors on our scoreboard list Sermorelin with a price we read on the product page (23 Sep 2026–1 Nov 2026). Of those, 25 name their testing laboratory, 21 publish certificates that resolve on the lab's own site, and 24 publish measured milligrams against the label. The full ranking, with every dated price, is on Best Sermorelin Vendors.
| Vendor | Rubric | Lab named | Price read |
|---|---|---|---|
| MyPurePeptidepartner | 10/10 | Janoshik Analytical | $25.00 · 5mg · 1 Nov 2026 |
| Panda Peptides | 10/10 | Janoshik Analytical · ILS Labs (per batch) | $40.00 · 10mg · 25 Oct 2026 |
| Peptide Giantspartner | 10/10 | Janoshik Analytical · Vanguard Laboratory | $35.00 · 5mg · 1 Nov 2026 |
| Premier Bio Labs | 10/10 | ILS Laboratories + Freedom Diagnostics | $43.00 · 5mg · 1 Nov 2026 |
| Purgo Labspartner | 10/10 | SteriGenix · Freedom Diagnostics | $59.99 · 10mg · 1 Nov 2026 |
Top 5 by rubric score; 20 more on the ranking page.
Sermorelin certificates we have opened
None yet for Sermorelin specifically. The COA library holds the certificates we have read for each vendor on other compounds, which is the next best signal of how that vendor documents a lot.
Side-effect questions
Side-effect section last reviewed 2026-09-12. Moved from the standalone side-effects page on 10 October 2026; text unchanged.
Regulatory
Is Sermorelin legal?
FDA-approved (prescription only)Sermorelin acetate is FDA-approved as a prescription drug for diagnostic evaluation of growth hormone deficiency. As a research chemical, it is available for laboratory research purposes. It is not a controlled substance but requires a prescription for clinical use.
US Status
Research Chemical
Legal to purchase for research
DEA Schedule
Not Scheduled
Not a controlled substance
FDA Status
Not Approved
FDA-approved for diagnostic use (prescription required)
Status by country
| Jurisdiction | Status as stated |
|---|---|
| United States | FDA-approved as a prescription drug (Geref). Not a controlled substance. Available as a research chemical for laboratory use. Compounding pharmacies may prepare it under physician supervision. |
| Canada | Not approved by Health Canada for clinical use but available for research. Not a scheduled substance. |
| United Kingdom | Not licensed by the MHRA for clinical use in the UK. Available for research purposes. |
| Australia | Available via the TGA Special Access Scheme for clinical use. Research use is permitted. |
| European Union | Not approved by the EMA as a medicinal product. Available for research purposes in most member states. |
Statements above are as our legal-status page for Sermorelin stated them in 2025; they were moved here on 10 October 2026 and were not re-verified in the move. Regulations change. This is general information, not legal advice; check the current position with your own jurisdiction's regulator before relying on it.
Legal questions
Is sermorelin a controlled substance?
No. Sermorelin is not listed as a controlled substance under the DEA Controlled Substances Act. It is a prescription drug in the US but not scheduled.
Do I need a prescription for sermorelin?
For clinical human use, yes — sermorelin is a prescription drug in the United States. For research purposes, it is available as a research chemical without a prescription.
Is sermorelin banned in sports?
Yes. Sermorelin is prohibited by WADA as a growth hormone releasing factor (GHRF).
Can compounding pharmacies make sermorelin?
Yes. Compounding pharmacies in the US may prepare sermorelin under physician supervision for individual patients, though the FDA has restricted its use in certain compounded preparations.
Is sermorelin legal in Australia?
Sermorelin may be accessed via the TGA Special Access Scheme for clinical use in Australia under physician supervision.
Research Guides
Related Research Guides
Everything we publish on Sermorelin
More on Sermorelin: comparisons, interactions, where to buy
Supporting Research
Limited Human DataLimited Human Data (small PD studies; historical pediatric approval)
Evidence note: Human evidence is limited to small pharmacodynamic studies. No large randomized controlled trials have established efficacy for anti-aging, body composition, or any indication in healthy adults.
Sermorelin has small human pharmacodynamic studies showing GH/IGF-1 elevation and body composition effects in older adults, plus a historical FDA approval for pediatric GH deficiency (withdrawn 2002 for commercial reasons, not safety). No large outcome RCTs exist for anti-aging or body composition endpoints.
References
- Vittone J, et al.HUMAN STUDY, n=16, elderly menEffects of single nightly injections of growth hormone-releasing hormone (GHRH 1-29) in healthy elderly men. Metabolism. 1997. PubMedNightly sermorelin increased IGF-1 and improved body composition in elderly men over 6 months.
- Walker RF.REVIEWSermorelin: a better approach to management of adult-onset growth hormone insufficiency?. Clin Interv Aging. 2006. PubMedSermorelin restores physiological GH pulsatility and is well-tolerated in adult GH insufficiency.
Research Databases
PubMed
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