Sermorelin

Sermorelin (5mg) — GHRH Analogue Growth Hormone Research Peptide

Omega Peptides Australia supplies Sermorelin (5mg) in Australia from domestic stock, dispatching same day on orders placed before 12pm with a certificate of analysis published for every batch. Often written GHRH 1-29, sermorelin peptide or sermorelin acetate, it is the 29-amino-acid GHRH fragment studied for growth hormone secretagogue research.

Sermorelin is a synthetic 29-amino-acid peptide that reproduces the first 29 residues of human growth hormone-releasing hormone (GHRH), the shortest fragment of the native 44-residue hormone that retains full activity at the GHRH receptor. It carries a C-terminal amide and is normally supplied as the acetate salt. In the literature and in supplier catalogues it is written as GRF 1-29, GHRH (1-29) or sermorelin acetate, and it was marketed for a time under the brand name Geref, which is why the name still appears in older papers and search results.

Sermorelin is studied as a reference GHRH-receptor agonist in three main areas: the physiology of pulsatile growth hormone secretion from the pituitary, the age-related decline in hypothalamic GHRH drive in somatotroph-axis models, and the way GHRH analogues and ghrelin-receptor secretagogues interact when combined in the same research model. At the receptor level it binds the GHRH receptor on anterior pituitary somatotrophs, a G-protein-coupled receptor that raises intracellular cyclic AMP and triggers both the synthesis and the release of growth hormone while leaving the body's normal somatostatin and IGF-1 feedback loops intact.

Omega Peptides Australia supplies sermorelin as a high-purity (≥99% HPLC) COA-verified lyophilised powder in a sealed 5mg vial. Orders placed before 12pm are dispatched the same day from within Australia, and the batch Certificate of Analysis for every lot is published in our COA library so the purity and identity of the vial you receive can be checked against the batch number on the label.

Key research areas

• Pulsatile growth hormone secretion. Sermorelin is the standard tool for studying how the pituitary releases growth hormone in bursts rather than at a constant rate. Because it acts through the same receptor as endogenous GHRH, it produces a physiological pulse that is still limited by somatostatin tone, which makes it useful for mapping the timing and amplitude of GH release in cell and animal models.
• Somatotroph-axis ageing models. A large body of work examines why GH output falls with age and whether the pituitary remains responsive when GHRH drive declines. Sermorelin is used in these models to separate a hypothalamic deficit from a pituitary one, since a preserved response to the analogue indicates that somatotroph cells are still functional.
• Diagnostic stimulation history. Sermorelin was originally developed and approved as a diagnostic agent, used to provoke a measurable GH response and characterise growth hormone deficiency. That history underpins its continued use as a benchmark GHRH stimulus in comparative endocrine research.
• Synergy with ghrelin-receptor secretagogues. GHRH analogues and growth hormone releasing peptides such as ipamorelin, GHRP-2 and hexarelin act through two different receptors on the same somatotroph. Research models routinely combine them to study the amplified, additive GH pulse that results, which is the rationale behind pairing a GHRH analogue with a secretagogue in laboratory work.
• Sleep and neuroendocrine rhythms. GHRH signalling is closely tied to slow-wave sleep and the nocturnal GH surge. Sermorelin is used to probe this relationship in sleep-physiology models and in studies of how circadian timing shapes pituitary output.
• Comparative GHRH analogue pharmacology. As the unmodified native fragment, sermorelin is the reference against which stabilised analogues such as Mod GRF 1-29 (CJC-1295 No DAC), CJC-1295 DAC and tesamorelin are compared for receptor potency, enzymatic degradation by DPP-IV and duration of action.

How Sermorelin works

Sermorelin is a full agonist at the growth hormone-releasing hormone receptor (GHRHR), which sits on somatotroph cells in the anterior pituitary. Receptor binding activates the stimulatory G protein, adenylyl cyclase converts ATP to cyclic AMP, and protein kinase A then drives two things at once: immediate exocytosis of stored GH granules and increased transcription of the GH gene so the stores are replenished. Because the analogue works upstream of the pituitary rather than replacing growth hormone itself, the downstream response remains subject to somatostatin inhibition and to negative feedback from IGF-1, and the pulse profile stays episodic rather than flat.

The native 29-residue sequence is rapidly cleaved by dipeptidyl peptidase-IV at the Ala2 position and by other plasma proteases, giving sermorelin a plasma half-life in the order of minutes and a short, sharp action. This is the main distinction from its relatives. Mod GRF 1-29 (CJC-1295 No DAC) carries four amino-acid substitutions that block that cleavage and extend the half-life to roughly half an hour, CJC-1295 DAC adds a lysine linker that binds serum albumin and extends action to days, and tesamorelin is the full 44-residue GHRH with a hexenoyl group on the N-terminus. Sermorelin, by contrast, is the unmodified reference compound.

Specifications

Available sizes and pricing

Sermorelin is currently supplied in a single 5mg vial size. The price below is per vial, with the equivalent per-milligram figure for comparison against other GHRH analogues in the range. Laboratories that also need reconstitution supplies can add the Research Starter Kit, which bundles bacteriostatic water, syringes and alcohol swabs.

• 5mg vial — $89.99 (about $18.00 per mg)

Quality and COA verification

Every batch of sermorelin is tested independently by Janoshik Analytical before it is released. Testing covers HPLC purity, which quantifies the target peptide against any truncated or deamidated impurities, and mass spectrometry identity, which confirms the molecular mass matches the expected 29-residue sequence. A Certificate of Analysis is issued for each lot and published in our COA library, where it can be matched to the batch number printed on the vial. The peptide is lyophilised for stability and sealed in a sterile glass vial under a crimped cap, then packed with cushioning for domestic transit so the powder arrives intact and dry. Retaining the vial in its lyophilised state until the point of use gives the longest shelf life.

Frequently bought together

• Bacteriostatic Water (10mL) — $29.99, the recommended diluent for reconstituting lyophilised sermorelin.
• Ipamorelin (10mg) — $89.99, a selective ghrelin-receptor secretagogue studied alongside GHRH analogues for additive GH-pulse research.
• CJC-1295 (DAC) (5mg) — $89.99, the long-acting GHRH analogue used as a duration-of-action comparator to sermorelin.
• Tesamorelin (10mg) — $139.99, the stabilised full-length GHRH 1-44 analogue for comparative receptor studies.

Research guides

• Sermorelin research guide
• CJC-1295 and Ipamorelin research guide
• CJC-1295 and Ipamorelin research overview
• Peptide storage guide
• COA testing explained
• Peptide reconstitution calculator
• Certificates of Analysis library

Frequently asked questions

What is Sermorelin?
Sermorelin is a synthetic peptide made up of the first 29 amino acids of human growth hormone-releasing hormone. It is the shortest fragment of GHRH that still fully activates the GHRH receptor, and it is used in research as a reference agonist for studying pituitary growth hormone release. It is supplied here as a lyophilised, COA-verified powder for in-vitro and laboratory research only.

What is Sermorelin also known as?
It is also written as GRF 1-29, GHRH (1-29) or GHRH 1-29 amide, and as sermorelin acetate when the salt form is specified. The historical brand name Geref is still used in some references. Common misspellings include sermoralin, sermorellin and semorelin, all of which refer to the same 29-residue GHRH fragment.

How does Sermorelin work?
Sermorelin binds the GHRH receptor on somatotroph cells in the anterior pituitary. This G-protein-coupled receptor raises cyclic AMP inside the cell, which triggers release of stored growth hormone and increases transcription of the GH gene. Because it acts upstream of the pituitary, the resulting GH pulse remains subject to normal somatostatin and IGF-1 feedback, which is why it is valued as a physiological stimulus in research models.

What does the research show about Sermorelin?
Sermorelin has a long research record as a diagnostic GHRH stimulus and as a tool compound in endocrine studies. Work in cell and animal models shows that it produces episodic growth hormone pulses, that its effect is amplified when combined with a ghrelin-receptor secretagogue, and that its short native half-life distinguishes it from stabilised analogues. All findings described here relate to laboratory and preclinical research, not to any use outside that setting.

Can I buy Sermorelin at Chemist Warehouse or a pharmacy in Australia?
No. Sermorelin is not registered on the Australian Register of Therapeutic Goods and is not stocked as a retail product by Chemist Warehouse, Priceline or other pharmacy chains. The Geref brand was approved in the United States in 1997 and withdrawn from the market in 2008 for commercial reasons, and no equivalent product has been registered in Australia. The lyophilised research-grade sermorelin supplied here is a laboratory reagent, not a pharmacy product.

Can Australian compounding pharmacies supply Sermorelin?
A compounding pharmacy can only prepare a medicine for an individual patient on a practitioner's prescription and cannot sell peptides to the general public. Some Australian compounding pharmacies have prepared sermorelin under that framework, which is a clinical pathway with its own rules and is entirely separate from research supply. Omega Peptides Australia supplies the lyophilised research compound for in-vitro laboratory use only, and does not offer any compounded or clinical product.

How do you reconstitute Sermorelin?
Use bacteriostatic water. Draw the required volume into a sterile syringe and add it slowly down the inside wall of the vial so the stream does not hit the powder directly. Swirl gently until the solution is clear; do not shake, as agitation can damage the peptide. Refrigerate the reconstituted vial at 2–8°C and use it within 28 days. Our reconstitution calculator will convert vial size and water volume into a concentration.

How should Sermorelin be stored?
Keep the lyophilised vial in a refrigerator at 2–8°C for short-term storage or in a freezer at −20°C for long-term storage, protected from light and moisture. Avoid repeated freeze-thaw cycles. After reconstitution, keep the solution refrigerated at 2–8°C and use it within 28 days. Sermorelin in solution is sensitive to heat and to slow hydrolysis, so a stable cold chain matters more for this 29-residue peptide than for the shorter hexapeptide secretagogues.

Where can I buy Sermorelin in Australia?
Omega Peptides Australia holds sermorelin in domestic stock and dispatches orders placed before 12pm on the same business day, with tracked shipping within Australia. Every batch carries an independent Certificate of Analysis that you can view in the COA library before ordering. You can browse sermorelin alongside the rest of our research peptides range to compare related GHRH analogues and secretagogues.

What does Sermorelin cost in Australia?
Sermorelin is supplied in a 5mg vial at $89.99, which works out to about $18.00 per milligram. There is currently no larger vial size or bundle for this compound. Bacteriostatic water for reconstitution is sold separately at $29.99 for 10mL or $14.99 for 3mL, and the Research Starter Kit combines bacteriostatic water with syringes and swabs for laboratories setting up for the first time.

How do I get Sermorelin online in Australia?
Open the sermorelin product page, select the 5mg vial, add it to your cart and complete checkout. Orders placed before 12pm are dispatched the same business day from our Australian stock; later orders leave the next business day. Parcels travel by tracked domestic courier in plain, discreet packaging with no product description on the outside, and a tracking number is emailed as soon as the order ships.

Is Sermorelin legal in Australia?
Omega Peptides Australia supplies sermorelin strictly for lawful in-vitro laboratory research. It is not approved by the TGA for human or veterinary use and is not sold as a medicine or supplement. Purchasers are responsible for ensuring their intended use complies with all applicable laws, including any state or territory requirements that apply to the handling of research chemicals.

Sermorelin vs CJC-1295 (No DAC/Mod GRF 1-29): what is the difference?
Both are 29-residue GHRH analogues that act on the same receptor. Sermorelin is the unmodified native sequence and is cleaved quickly by DPP-IV, giving a half-life measured in minutes. Mod GRF 1-29, usually sold as CJC-1295 No DAC, substitutes four residues to block that cleavage, extending action to roughly half an hour. CJC-1295 DAC adds an albumin-binding linker for a multi-day duration. Researchers choose sermorelin when a short, physiological pulse is the goal.

⚠ For in-vitro research and laboratory use only. Not for human or veterinary use.