GHRP-6

GHRP-6 (10mg) — First-Generation Hexapeptide Growth Hormone Secretagogue Research Peptide

GHRP-6 (10mg) is supplied in Australia by Omega Peptides Australia from domestic stock, with same-day dispatch on orders placed before 12pm and an independent certificate of analysis for every batch. Commonly written as GHRP 6, GHRP6 or growth hormone releasing peptide 6, it is a hexapeptide growth hormone secretagogue studied for ghrelin receptor and appetite signalling.

GHRP-6 is a synthetic six-amino-acid peptide with the sequence His-D-Trp-Ala-Trp-D-Phe-Lys and a C-terminal amide. It was the first growth hormone releasing peptide to be characterised, emerging in the early 1980s from work on enkephalin analogues that unexpectedly stimulated growth hormone release, and it is the parent compound of the whole GHRP family. The later discovery of the receptor it acts on, and then of ghrelin as that receptor's natural ligand, both grew directly out of research on GHRP-6. It is written as GHRP6, GHRP 6 or ghrp 6 peptide, and its full name is growth hormone releasing peptide-6.

GHRP-6 is studied in three main directions: as the reference ghrelin-receptor agonist for pituitary growth hormone secretion, as one of the strongest peptide stimulants of appetite in feeding and energy-balance research, and as a tool for gastric motility and gut-brain signalling models. At the receptor level it activates the growth hormone secretagogue receptor type 1a (GHS-R1a), a G-protein-coupled receptor on pituitary somatotrophs and hypothalamic neurons, raising intracellular calcium so that stored growth hormone is released in a pulse.

Omega Peptides Australia supplies GHRP-6 as a high-purity (≥99% HPLC) COA-verified lyophilised powder in a sealed 10mg vial. Orders placed before 12pm are dispatched the same day from stock held 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

• Growth hormone secretagogue reference compound. As the first GHRP, GHRP-6 is the baseline against which every later secretagogue has been measured. It produces a clear, dose-dependent GH pulse in pituitary cell and animal models, and it is still the compound most often used to validate GHS-R1a expression or responsiveness in a new experimental system.
• Appetite and feeding behaviour. GHRP-6 is one of the most potent peptide stimulants of food intake in the models studied, an effect mediated through the ghrelin receptor in the hypothalamic arcuate nucleus. It is widely used in energy-balance research, cachexia models and studies that separate the orexigenic and endocrine actions of ghrelin signalling.
• Gastric motility and gut-brain signalling. GHS-R1a is expressed on vagal afferents and in the enteric nervous system, and GHRP-6 has been used to study gastric emptying, motility and the vagal pathway that links the stomach to the hypothalamus in rodent models.
• Ghrelin receptor discovery and pharmacology. The search for the target of GHRP-6 led to the cloning of GHS-R1a in the mid-1990s and then to the identification of ghrelin. GHRP-6 remains a standard ligand in receptor-binding, internalisation and signalling assays.
• Synergy with GHRH analogues. Because GHRP-6 acts on GHS-R1a while sermorelin, CJC-1295 and tesamorelin act on the GHRH receptor, the two classes are additive when combined. Pairing them is a standard design in secretagogue research and forms the basis of many blended GH-axis compounds.
• Cardiac and tissue-protection models. Preclinical rodent studies have examined GHRP-6 in models of cardiac ischaemia and tissue injury, exploring whether ghrelin-receptor signalling has protective actions that are independent of growth hormone.

How GHRP-6 works

GHRP-6 is an agonist at the growth hormone secretagogue receptor type 1a, a Gq-coupled receptor found on pituitary somatotrophs, in the arcuate nucleus of the hypothalamus and on vagal afferent neurons. Receptor activation stimulates phospholipase C, which produces inositol trisphosphate and diacylglycerol; inositol trisphosphate releases calcium from intracellular stores, and the calcium surge drives exocytosis of growth hormone granules from the somatotroph. In the hypothalamus the same receptor increases GHRH neuron activity and lowers somatostatin tone, so the pituitary receives more stimulation and less inhibition at once. This is why a GHRP produces a larger pulse than a GHRH analogue on its own and why the two classes are additive when combined.

GHRP-6 is the shortest-acting of the common GHRPs, with a reported plasma half-life of roughly 20 minutes, compared with about 30 minutes for GHRP-2 and about 50 minutes for hexarelin. Its D-tryptophan at position two is the residue that later chemists modified to make hexarelin, where it became 2-methyl-D-tryptophan, and GHRP-2, where it became a naphthylalanine, so both descendants are more potent GH releasers. What GHRP-6 keeps that they partly lose is a strong appetite response, which makes it the compound of choice in feeding research. Against ipamorelin, which is selective for GH and has almost no orexigenic effect, GHRP-6 is the less selective but more broadly acting reference compound.

Specifications

Available sizes and pricing

GHRP-6 is supplied in a single 10mg vial. As a hexapeptide with a molecular weight of about 873 g/mol, 10mg represents a high molar quantity of peptide. The price is per vial, with the per-milligram figure shown so it can be compared directly against GHRP-2, hexarelin and ipamorelin. Laboratories that need reconstitution supplies can add the Research Starter Kit, which bundles bacteriostatic water, syringes and alcohol swabs in one pack.

• 10mg vial — $79.99 (about $8.00 per mg)

Quality and COA verification

Every batch of GHRP-6 is tested independently by Janoshik Analytical before it is released. The HPLC purity assay quantifies the intact hexapeptide against any deletion sequences, diastereomers or oxidised tryptophan impurities, and mass spectrometry confirms that the measured molecular mass matches the expected value for the six-residue sequence. A Certificate of Analysis is issued for every lot and published in our COA library, where it can be matched to the batch number on the vial label. The peptide is lyophilised for long-term stability, sealed in a sterile glass vial with a crimped cap, and packed with cushioning for domestic transit so the powder arrives dry and intact. Keeping the vial lyophilised until use protects the two oxidation-sensitive tryptophan residues.

Frequently bought together

• Bacteriostatic Water (10mL) — $29.99, the recommended diluent for reconstituting lyophilised GHRP-6.
• GHRP-2 (10mg) — $79.99, the second-generation GHRP for direct potency and selectivity comparisons.
• Hexarelin (5mg) — $89.99, the stabilised derivative of GHRP-6 for side-by-side receptor studies.
• Ipamorelin (10mg) — $89.99, the selective secretagogue used as the specificity comparator to GHRP-6.

Research guides

• 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 GHRP-6?
GHRP-6 is a synthetic six-residue peptide and the first growth hormone releasing peptide ever characterised. It activates the ghrelin receptor on pituitary and hypothalamic cells to release growth hormone, and it is also one of the strongest peptide stimulants of appetite in research models. It is the parent compound of GHRP-2 and hexarelin. It is supplied here as a lyophilised, COA-verified powder for in-vitro laboratory research only.

What is GHRP-6 also known as?
It is also written as GHRP6, GHRP 6, ghrp-6 or ghrp 6 peptide, and its full name is growth hormone releasing peptide-6. When the salt form is specified it appears as GHRP-6 acetate. Its chemical description is L-histidyl-D-tryptophyl-L-alanyl-L-tryptophyl-D-phenylalanyl-L-lysinamide. Misspellings such as grhp-6 and ghrp six all refer to the same hexapeptide.

How does GHRP-6 work?
GHRP-6 binds the growth hormone secretagogue receptor type 1a, the receptor that ghrelin uses, on pituitary somatotrophs, in the hypothalamus and on vagal nerve fibres. Activation raises intracellular calcium through the Gq and phospholipase C pathway, triggering release of stored growth hormone. In the hypothalamus it increases GHRH output, reduces somatostatin tone and engages the feeding circuits of the arcuate nucleus, which is the basis of its strong appetite effect.

What does the research show about GHRP-6?
Decades of cell and animal work show that GHRP-6 reliably produces a growth hormone pulse, that it strongly increases food intake through the ghrelin receptor, that it transiently raises cortisol, and that its response attenuates with repeated exposure. Its discovery led directly to the cloning of the ghrelin receptor and the identification of ghrelin. All of this describes laboratory and preclinical research and does not relate to any use outside that setting.

Can I buy GHRP-6 at Chemist Warehouse or a pharmacy in Australia?
No. GHRP-6 is not registered on the Australian Register of Therapeutic Goods, has never been marketed as a medicine anywhere, and is not stocked by Chemist Warehouse, Priceline or any other retail pharmacy. The lyophilised research-grade GHRP-6 supplied here is a laboratory reagent for research use and is not a pharmacy product or a substitute for any registered medicine.

Can Australian compounding pharmacies supply GHRP-6?
An Australian compounding pharmacy may only prepare a medicine for a named patient on a practitioner's prescription and cannot sell peptides to the general public. Research suppliers such as Omega Peptides Australia supply the lyophilised research compound for in-vitro laboratory use, which is a separate product on a separate pathway from anything a pharmacy prepares.

How do you reconstitute GHRP-6?
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 strike the lyophilised cake directly. Swirl gently until the solution is clear and do not shake, as agitation can degrade the peptide. Refrigerate the reconstituted vial at 2–8°C and use it within 28 days. Our reconstitution calculator converts vial size and diluent volume into a working concentration.

How should GHRP-6 be stored?
Keep the unopened lyophilised vial at 2–8°C for short-term storage or at −20°C for long-term storage, protected from light and moisture and away from repeated freeze-thaw cycles. After reconstitution, keep the solution at 2–8°C and use it within 28 days. GHRP-6 contains two tryptophan residues that are sensitive to light and oxidation, so keep the vial in its box and limit the time it spends at room temperature.

Where can I buy GHRP-6 in Australia?
Omega Peptides Australia holds GHRP-6 in domestic stock and dispatches orders placed before 12pm on the same business day with tracked shipping within Australia. Each batch is backed by an independent Certificate of Analysis that you can review in the COA library before ordering. GHRP-6 is listed alongside GHRP-2, hexarelin and ipamorelin in our research peptides range so related secretagogues can be compared on one page.

What does GHRP-6 cost in Australia?
GHRP-6 is supplied in a 10mg vial at $79.99, which is about $8.00 per milligram, placing it among the most economical secretagogues in the range on a per-milligram basis. There is currently no larger vial or bundle for this compound. Bacteriostatic water is sold separately at $29.99 for 10mL or $14.99 for 3mL, and the Research Starter Kit adds syringes and alcohol swabs for laboratories setting up for the first time.

How do I get GHRP-6 online in Australia?
Open the GHRP-6 product page, select the 10mg vial, add it to the cart and complete checkout. Orders placed before 12pm are dispatched the same business day from our Australian stock and later orders leave on 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 GHRP-6 legal in Australia?
Omega Peptides Australia supplies GHRP-6 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 research chemicals.

GHRP-6 vs GHRP-2 and Ipamorelin: which is used for what in research?
All three are GHS-R1a agonists. GHRP-6 is the original compound, chosen when a strong appetite response or a well-characterised reference ligand is needed, with a half-life of about 20 minutes. GHRP-2 is more potent at releasing growth hormone with a milder appetite effect, so it suits studies focused on the GH pulse itself. Ipamorelin is the most selective, releasing GH with minimal effect on cortisol, prolactin or feeding, which makes it the choice for clean endocrine models.

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