Sermorelin
Growth Hormone / IGF-1 AxisFDA ApprovedAlso known as: GRF 1-29
Sermorelin acetate is a synthetic 29-amino-acid peptide corresponding to the biologically active N-terminal fragment of human growth hormone-releasing hormone (GHRH 1-29). It was one of the first GHRH analogs to achieve FDA approval — Geref received pediatric approval in 1997 for evaluating and treating idiopathic growth hormone deficiency in children.
Overview
At A Glance
GHRH Receptor Pharmacology…
Mechanism of Action
GHRH Receptor Pharmacology
Sermorelin is a truncated analog - the first 29 amino acids - of the 44-amino-acid native GHRH produced by the arcuate nucleus of the hypothalamus. The 1-29 fragment retains essentially the full growth-hormone-releasing activity of the parent hormone; the C-terminal residues 30-44 contribute to stability but are not required for receptor binding or activation [PMID:8772599].
When sermorelin binds the GHRH receptor (GHRHR) - a class B G-protein-coupled receptor expressed on anterior-pituitary somatotrophs - it triggers:
- Gs-protein activation increased cyclic AMP protein kinase A signaling
- Transcription of the GH1 gene and exocytosis of stored GH secretory granules
- Synergy with the ghrelin/GHS-R1a pathway when a growth-hormone secretagogue (e.g., ipamorelin) is co-administered
The net effect is a pulsatile release of the body's own growth hormone rather than the flat, supraphysiologic exposure produced by injecting recombinant HGH, which bypasses the pituitary entirely.
Pulsatility and the Somatostatin Gate
GHRH-driven GH release remains subject to somatostatin tone. Somatostatin - released from the periventricular nucleus of the hypothalamus - sets a ceiling on how much GH any single GHRH pulse can elicit. This is why sermorelin cannot drive GH to the supraphysiologic levels achievable with exogenous HGH, and why it preserves the natural ultradian rhythm of GH secretion. Dose-response work in older men showed GH and IGF-1 output rise with dose and then plateau, consistent with this somatostatin ceiling [PMID:1379256].
Short Half-Life as a Feature
Native GHRH has a plasma half-life of roughly 7 minutes; sermorelin clears with a half-life on the order of 10-20 minutes. This rapid clearance:
- Limits receptor desensitization that continuous GHRH exposure would cause
- Allows somatostatin pulses to suppress GH between cycles
- Reproduces the brief GHRH pulses that occur naturally in young adults
This is also why sermorelin must be dosed daily, whereas long-acting analogs such as CJC-1295-DAC extend the dosing interval but sacrifice the pulsatile pharmacology.
Downstream Effects
Nightly sermorelin (or the closely related GHRH(1-29) analogs used in trials) raises IGF-1 within the physiologic range rather than above it. In the main controlled adult trial, IGF-1 rose ~28% and skin thickness increased in both sexes, while lean-body-mass, insulin-sensitivity, general well-being and libido improvements were seen in men only [PMID:9141536][PMID:9360512]. Effects reported across the literature (with varying strength of evidence) include:
- Modest lean-mass gains and small reductions in body fat (male-predominant in the controlled data)
- A tendency toward improved slow-wave (NREM) sleep - GHRH is itself a sleep-regulatory peptide, and the largest physiologic GH pulse occurs during early slow-wave sleep
- Subjective improvements in recovery and skin quality
These should be read as physiologic restoration toward a more youthful GH secretion pattern - not the supraphysiologic anabolism of recombinant HGH or anabolic steroids. Notably, single-nightly dosing produced no measurable IGF-1 or body-composition change in one 6-week trial [PMID:9005976], so real-world response is variable and dosing schedule matters.
Overview
Sermorelin acetate is a synthetic 29-amino-acid peptide corresponding to the biologically active N-terminal fragment of human growth hormone-releasing hormone (GHRH 1-29). It was one of the first GHRH analogs to achieve FDA approval — Geref received pediatric approval in 1997 for evaluating and treating idiopathic growth hormone deficiency in children. Although the branded product was discontinued commercially in 2008 due to market factors unrelated to safety or efficacy, sermorelin has experienced a significant second life through 503B compounding pharmacies that supply it for off-label use in adult growth hormone axis support, anti-aging medicine, and athletic performance contexts.
Sermorelin binds the GHRH receptor (GHRHR) on pituitary somatotrophs and triggers endogenous growth hormone release through the body's native negative-feedback architecture. Because it relies on pituitary reserve rather than bypassing it, sermorelin produces pulsatile GH release that respects somatostatin inhibition — you cannot overshoot the way exogenous recombinant human GH can, and IGF-1 typically rises into the upper quartile of age-adjusted normal rather than into supraphysiological territory. This is the fundamental mechanistic difference that makes GHRH therapy tolerable for long-term use where rhGH use carries more concerning risks.
Its short serum half-life — approximately 10 to 20 minutes in healthy adults — is simultaneously sermorelin's greatest limitation and its most clinically elegant feature. The short window forces once-daily bedtime dosing that aligns with the body's natural nocturnal GH pulse, and it means residual peptide never persists long enough to disturb subsequent endogenous pulses. Modern practitioners frequently choose sermorelin over longer-acting analogs like CJC-1295 DAC specifically because the pulsatile kinetics more closely mimic healthy young physiology.
In research and clinical settings, sermorelin is typically dosed at 200 to 500 mcg subcutaneously at bedtime for adult GH tuning protocols, though historical pediatric GHD protocols used up to 30 mcg/kg/day. Six-month trials in healthy older adults have demonstrated modest but measurable gains in lean body mass, reductions in visceral adiposity, and improvements in sleep architecture — particularly slow-wave sleep depth, which is where the majority of physiologic GH secretion occurs in the first place.
Potential Research Fields
Chemical Information
IUPAC Name
Growth hormone-releasing hormone (1-29) amide
CAS Number
86168-78-7
Molecular Formula
C149H246N44O42S
Molecular Mass
3357.9 g/mol
Amino Acid Sequence
Dosing & Protocols
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Interactions
Interaction Matrix
Contraindications
Sermorelin is contraindicated or requires extreme caution in:
- Active malignancy — particularly any hormone-responsive cancer (breast, prostate, endometrial) given the theoretical concern that elevated IGF-1 could promote tumor growth
- Strong family history of GH-axis responsive cancers — use only under specialist supervision with close monitoring
- Pregnancy and lactation — no established safety data; avoid
- Known hypersensitivity to sermorelin, GHRH analogs, or any excipient
- Severe untreated sleep apnea — theoretical concern about upper airway soft tissue growth; stabilize with CPAP/APAP before initiating
- Acute critical illness — GH-axis stimulation is inappropriate during sepsis, post-surgical recovery, multiple trauma, or respiratory failure states
- Diabetic ketoacidosis or severe uncontrolled diabetes — resolve the metabolic state first
- Active proliferative retinopathy — relative contraindication; discuss with ophthalmologist
Relative cautions requiring monitoring:
- Borderline fasting glucose or HbA1c — monitor closely; discontinue if deterioration
- History of benign adenomas (pituitary, adrenal, thyroid) — imaging surveillance recommended
- Strong family history of colon polyps — baseline colonoscopy before starting, surveillance per gastroenterology guidance
- Concurrent glucocorticoid therapy — pharmacodynamic interference; GH-axis stimulation is less effective in pharmacologic steroid contexts
Age-related note: Sermorelin has been used in pediatric GHD populations historically with FDA approval, but use in healthy older adults for anti-aging purposes remains off-label and should only be undertaken with informed consent about the limitations of available long-term safety data.
Research Disclaimer
This interaction data is compiled from published research and community reports. It may not be exhaustive. Always consult a healthcare professional before combining compounds.
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| Vendor | Product | Form | Qty | Price | $/mg | Coupon | |
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Sermorelin 5mg | vial | 1 vial● Out of Stock | $39.00BEST | $7.800 | — | Sign in for stock alert |
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Sermorelin 10mg | vial | 1 vial● In Stock | $65.00 | $6.500 | — | |
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Sermorelin 5mg | vial | 1 vial● In Stock | $39.99 | $7.998 | — | |
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Sermorelin 2mg | vial | 2mg vial● In Stock | $24.99 | $12.495 | ||
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Sermorelin 5mg | vial | 5mg vial● In Stock | $39.99 | $7.998 |
Tracking since Mar 13, 2026 · 7 data points
Price History
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Related Compounds
View AllCJC-1295 (Mod GRF 1-29)
Growth Hormone / IGF-1 AxisPreclinicalCJC-1295 without DAC (also called Modified GRF 1-29 or MOD-GRF 1-29) is a 30-amino-acid analog of the first 29 residues of endogenous Growth Hormone Releasing Hormone (GHRH), with four strategic substitutions (D-Ala² for DPP-4 resistance, Gln⁸, Ala¹⁵, Leu²⁷) that extend its plasma half-life from <2 minutes (native GHRH) to ~30 minutes.
CJC-1295 with DAC
Growth Hormone / IGF-1 AxisPhase 2CJC-1295 with DAC (Drug Affinity Complex) is a modified form of CJC-1295 that incorporates a maleimidopropionic acid (MPA) reactive group at the C-terminus.
CJC-1295 with DAC
Growth Hormone / IGF-1 AxisPreclinical / Research peptideCJC-1295 with DAC is the long-acting variant of CJC-1295.
GHRP-2
Growth Hormone / IGF-1 AxisPhase 2GHRP-2 (growth hormone-releasing peptide-2), also known as pralmorelin and KP-102, is a synthetic hexapeptide growth hormone secretagogue that was among the first GHRPs developed in the seminal research of Cyril Bowers and colleagues at Tulane University in the late 1980s and early 1990s.
GHRP-6
Growth Hormone / IGF-1 AxisPhase 2GHRP-6 (growth hormone-releasing peptide-6) is a synthetic hexapeptide with the sequence His-D-Trp-Ala-Trp-D-Phe-Lys-NH2 that binds the ghrelin receptor (GHS-R1a) to stimulate endogenous growth hormone release.
Hexarelin
Growth Hormone / IGF-1 AxisPhase 2Hexarelin (also called examorelin) is a potent synthetic hexapeptide growth hormone secretagogue with the sequence His-D-2-methyl-Trp-Ala-Trp-D-Phe-Lys-NH2.
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Related Articles
All PostsResearch Score
198 PubMed studies
Quality Indicators
Data Completeness
100%Research Credibility
Well-researched compound
Quick Facts
Half-Life
~10-20 minutes (plasma; native GHRH 7 minutes)
Molecular Weight
3357.9 g/mol
CAS Number
86168-78-7
Trial Phase
FDA Approved
Safety Profile
Low RiskCommon Side Effects
- • Injection site redness/swelling
- • Headache
- • Flushing
- • Nausea
Stop Use If
- Active malignancy
- Hypothyroidism (treat first)
- Pituitary tumor
Research Disclaimer
This information is for educational and research purposes only. Not intended as medical advice. Consult a healthcare professional before use.
Frequently Asked Questions
What is sermorelin and how does it work?
Sermorelin is a synthetic 29-amino-acid peptide corresponding to the biologically active N-terminal fragment of GHRH - the hypothalamic hormone that tells your pituitary to release growth hormone. It binds the GHRH receptor on pituitary somatotrophs, triggering a pulsatile release of endogenous GH that respects the body's natural negative feedback architecture. It was originally FDA-approved as Geref in 1997 for pediatric growth hormone deficiency evaluation and treatment, and is now commonly used off-label through 503B compounding pharmacies for adult GH optimization. Unlike recombinant HGH, sermorelin cannot produce supraphysiologic GH levels because somatostatin limits how much GH any single GHRH pulse can elicit.
How is sermorelin different from CJC-1295?
Sermorelin is pure GHRH(1-29) with a 10-20 minute half-life. CJC-1295 without DAC is a stabilized GHRH analog with a modestly longer half-life (~30 minutes), and CJC-1295 DAC adds a DAC linker that extends half-life to ~8 days. Sermorelin and no-DAC CJC-1295 produce pulsatile GH release; CJC-1295 DAC produces continuous GHRH-receptor stimulation that raises baseline GH and IGF-1 more dramatically but eliminates pulsatility. For users prioritizing the most physiologic secretion pattern and minimum receptor desensitization risk, sermorelin is the most conservative choice. For users prioritizing convenience (once or twice weekly dosing), CJC-1295 DAC wins. See the CJC-1295 page for a detailed side-by-side.
What results should I expect from sermorelin?
Be realistic - the controlled human data are modest. In the main adult trial of GHRH(1-29) (Khorram 1997), IGF-1 rose about 28% and skin thickness increased in both sexes, but lean body mass and quality-of-life gains appeared in men only, and a separate 6-week trial of single nightly dosing found no IGF-1 or body-composition change at all. So expect a modest IGF-1 rise into the upper-normal range, possibly small improvements in body composition, recovery, sleep depth and skin quality over 12-16 weeks, and nothing resembling recombinant HGH or anabolic steroids. Sermorelin is best understood as nudging your own GH secretion back toward a more youthful pattern rather than delivering supraphysiologic GH. Individual response varies widely.
What is the best sermorelin dosage?
The typical adult protocol is 200-500 mcg subcutaneously once nightly at bedtime. Beginners start at 200-300 mcg to assess tolerance. After 6-12 weeks, responders typically titrate to 300-500 mcg based on IGF-1 response. The single-dose ceiling is around 500 mcg - above that, somatostatin tone prevents further GH release, so higher doses are simply wasted peptide. Some advanced users split the dose into a morning and evening injection, though the bedtime-only approach remains the most common and best-studied. Always dose in a fasted state (3+ hours after last meal) to avoid the insulin-driven somatostatin surge that would blunt GH release.
Can I stack sermorelin with ipamorelin?
Yes - sermorelin + ipamorelin is the classic and most well-established GHRH + GHS combination in the peptide space. The two compounds bind different receptors on the same pituitary somatotrophs (GHRHR and GHS-R1a respectively) and produce a 3-5x amplification of GH pulse amplitude compared to either compound alone (Bowers 1991). Typical stack dose is sermorelin 200-300 mcg + ipamorelin 200-300 mcg in the same subcutaneous injection at bedtime. Ipamorelin's selectivity - it does not elevate cortisol, prolactin, or ACTH - makes it the cleanest ghrelin mimetic to pair with sermorelin. See ipamorelin for full details.
Is sermorelin still FDA approved?
Sermorelin acetate received FDA approval in 1997 as Geref for evaluation of pediatric growth hormone deficiency. The branded product was discontinued commercially in 2008 due to market factors - not safety or efficacy concerns. The peptide itself remains legally available through 503B compounding pharmacies that produce it for physicians who prescribe it off-label for adult GH optimization. This legal-but-compounded status is similar to many other legacy peptides. Clinical use is supervised by medical professionals, and the quality-controlled compounded version is considered equivalent to the original Geref for pharmacologic purposes.
How long does it take sermorelin to work?
The GH and IGF-1 response to a single sermorelin injection occurs within minutes - peak serum GH typically occurs 15-30 minutes post-injection. However, the clinically meaningful body composition and subjective effects take 6-16 weeks of consistent nightly dosing to become apparent. IGF-1 stabilizes at its new elevated setpoint around week 4-6. Lean body mass changes are detectable by week 8-12. Sleep quality improvements often show up earliest - many users report enhanced slow-wave sleep within 2-3 weeks of consistent dosing. Skin changes (improved thickness, hydration) take 12-16 weeks to measure but are usually subjectively noticed earlier.
What are the side effects of sermorelin?
Most side effects are mild and transient. The most common are injection site reactions (erythema, mild itching), facial flushing immediately after injection (fades within 10-20 minutes), and occasionally vivid dreams - which isn't necessarily adverse given that sermorelin improves slow-wave sleep where dreams are consolidated. Less common effects include mild headache, transient hunger (less pronounced than with ghrelin mimetics), and minor fluid retention in the first weeks. Theoretical long-term concerns relate to sustained IGF-1 elevation and cancer risk, though no causal link has been demonstrated in trials to date. Stop if you develop persistent joint pain, carpal tunnel symptoms, or peripheral edema - these suggest IGF-1 is too high.
Does sermorelin cause weight loss?
Sermorelin is not primarily a weight-loss compound. It produces modest reductions in visceral and subcutaneous fat over 12-16 weeks - typically 1-3% body fat in responders - alongside lean mass gains of similar magnitude. Users looking for dramatic weight loss should consider GLP-1 receptor agonists like semaglutide, tirzepatide, or retatrutide. Sermorelin is better understood as a body-composition-optimization tool that modestly improves the fat-to-lean ratio rather than a fat-loss drug. If visceral adiposity specifically is the target, tesamorelin has FDA-approved trial data showing roughly 18% VAT reduction over 26 weeks, which is substantially more aggressive than sermorelin achieves.
Where can I buy sermorelin legally?
In the United States, sermorelin can be prescribed legally by licensed physicians and dispensed through 503B compounding pharmacies. This is the proper legal pathway - the prescribing physician oversees dosing, labs, and safety monitoring. There is also a gray-market research-chemical supply chain outside of medical oversight, but this path carries significant quality-control, sterility, and legal risk. Prescribed compounded sermorelin through a qualified clinic is the only path we recommend. For a curated list of peptide-friendly clinical practices and reliable compounded-peptide pharmacies, see our best vendors guide for 2026.
Research Tools
Related Compounds
View AllCJC-1295 (Mod GRF 1-29)
Growth Hormone / IGF-1 AxisPreclinicalCJC-1295 without DAC (also called Modified GRF 1-29 or MOD-GRF 1-29) is a 30-amino-acid analog of the first 29 residues of endogenous Growth Hormone Releasing Hormone (GHRH), with four strategic substitutions (D-Ala² for DPP-4 resistance, Gln⁸, Ala¹⁵, Leu²⁷) that extend its plasma half-life from <2 minutes (native GHRH) to ~30 minutes.
CJC-1295 with DAC
Growth Hormone / IGF-1 AxisPhase 2CJC-1295 with DAC (Drug Affinity Complex) is a modified form of CJC-1295 that incorporates a maleimidopropionic acid (MPA) reactive group at the C-terminus.
CJC-1295 with DAC
Growth Hormone / IGF-1 AxisPreclinical / Research peptideCJC-1295 with DAC is the long-acting variant of CJC-1295.
GHRP-2
Growth Hormone / IGF-1 AxisPhase 2GHRP-2 (growth hormone-releasing peptide-2), also known as pralmorelin and KP-102, is a synthetic hexapeptide growth hormone secretagogue that was among the first GHRPs developed in the seminal research of Cyril Bowers and colleagues at Tulane University in the late 1980s and early 1990s.
GHRP-6
Growth Hormone / IGF-1 AxisPhase 2GHRP-6 (growth hormone-releasing peptide-6) is a synthetic hexapeptide with the sequence His-D-Trp-Ala-Trp-D-Phe-Lys-NH2 that binds the ghrelin receptor (GHS-R1a) to stimulate endogenous growth hormone release.
Hexarelin
Growth Hormone / IGF-1 AxisPhase 2Hexarelin (also called examorelin) is a potent synthetic hexapeptide growth hormone secretagogue with the sequence His-D-2-methyl-Trp-Ala-Trp-D-Phe-Lys-NH2.
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