What is GHRP-6?

An early synthetic hexapeptide ghrelin-receptor agonist that releases growth hormone and strongly increases appetite.

GHRP-6 in the library · Growth Hormone Secretagogues · Metabolic & Weight Peptides · Human Trials · What are peptides?

0 registered trials · 45 indexed papers · 178 human / 387 animal studies

From the PeptideWhiz library entry. "As described" sections summarize claims made in the sources; they are not PeptideWhiz endorsements.

What it is

GHRP-6 is described as one of the first synthetic growth hormone secretagogues (His-D-Trp-Ala-Trp-D-Phe-Lys-NH2), developed before ghrelin itself was discovered.

It has been used in clinical research as a diagnostic stimulus for GH secretion, and is known for a marked hunger effect.

Mechanism (as described)

It activates the ghrelin receptor (GHS-R1a); its GH release is greatest when the body's own GHRH is present (Pandya et al., 1998).
Besides GH, it can raise prolactin and cortisol modestly, which is one reason later secretagogues such as ipamorelin were developed.

Evidence (as described)

Human studies include a pharmacokinetic study in nine healthy men (Cabrales et al., 2013) and combined GHRH + GHRP-6 testing for adult GH deficiency (Popovic et al., Lancet 2000).
No trial is described as showing long-term body-composition or performance benefit.

Status

Not approved as a medicine.

Peer-reviewed studies (45)

Paper	Authors	Journal	Year	Type
Phase III Open-Label, Randomized Clinical Trial of Epidermal Growth Factor and Growth Hormone Releasing Hexapeptide in Acute Ischemic Stroke	Hernández-Bernal F et al.	Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia	2026	Randomized Controlled Trial
Insulinotropic action of bombesin-like peptides mediated by gastrin-releasing peptide receptors in steers	Zhao HQ et al.	Journal of animal science	2016	Randomized Controlled Trial
Pharmacokinetic study of Growth Hormone-Releasing Peptide 6 (GHRP-6) in nine male healthy volunteers	Cabrales A et al.	European journal of pharmaceutical sciences : official journal of the European Federation for Pharmaceutical Sciences	2013	Clinical Trial, Phase I
Bombesin-like peptides stimulate growth hormone secretion mediated by the gastrin-releasing peptide receptor in cattle	Zhao H et al.	Peptides	2012	Randomized Controlled Trial
Effects of ghrelin, GH-releasing peptide-6 (GHRP-6) and GHRH on GH, ACTH and cortisol release in hyperthyroidism before and after treatment	Molica P et al.	Pituitary	2010	Clinical Trial
Effects of ghrelin, growth hormone-releasing peptide-6, and growth hormone-releasing hormone on growth hormone, adrenocorticotropic hormone, and cortisol release in type 1 diabetes mellitus	de Sá LB et al.	Metabolism: clinical and experimental	2010	Randomized Controlled Trial
Diagnosis of adrenal insufficiency using the GHRP-6 Test: comparison with the insulin tolerance test in patients with hypothalamic-pituitary-adrenal disease	Alaioubi B et al.	Hormone and metabolic research = Hormon- und Stoffwechselforschung = Hormones et metabolisme	2010	Clinical Trial
Adrenocorticotrophic hormone (ACTH) responsiveness to ghrelin increases after 6 months of ketoconazole use in patients with Cushing's disease: comparison with GH-releasing peptide-6 (GHRP-6)	Correa-Silva SR et al.	Clinical endocrinology	2010	Randomized Controlled Trial
Ghrelin and GHRP-6-induced ACTH and cortisol release in thyrotoxicosis	Nascif SO et al.	Pituitary	2009	Controlled Clinical Trial
Association between tumoral GH-releasing peptide receptor type 1a mRNA expression and in vivo response to GH-releasing peptide-6 in ACTH-dependent Cushing's syndrome patients	Machado MC et al.	European journal of endocrinology	2008	Clinical Trial
Decreased ghrelin-induced GH release in thyrotoxicosis: comparison with GH-releasing peptide-6 (GHRP-6) and GHRH	Nascif SO et al.	Pituitary	2007	Randomized Controlled Trial
Decreased GH secretion and enhanced ACTH and cortisol release after ghrelin administration in Cushing's disease: comparison with GH-releasing peptide-6 (GHRP-6) and GHRH	Correa-Silva SR et al.	Pituitary	2006	Controlled Clinical Trial
Hexarelin decreases slow-wave sleep and stimulates the secretion of GH, ACTH, cortisol and prolactin during sleep in healthy volunteers	Frieboes RM et al.	Psychoneuroendocrinology	2004	Controlled Clinical Trial
Growth hormone response to GHRH + GHRP-6 in type 2 diabetes during euglycemic and hyperglycemic clamp	Micic D et al.	Diabetes research and clinical practice	2004	Clinical Trial
Comparison between insulin tolerance test, growth hormone (GH)-releasing hormone (GHRH), GHRH plus acipimox and GHRH plus GH-releasing peptide-6 for the diagnosis of adult GH deficiency in normal subjects, obese and hypopituitary patients	Cordido F et al.	European journal of endocrinology	2003	Clinical Trial
Growth-hormone response to combined stimulation with GHRH plus GH-releasing peptide-6 in obese patients with polycystic ovary syndrome before and after short-term fasting	Micić D et al.	Journal of endocrinological investigation	2003	Controlled Clinical Trial
GHRP-6 is able to stimulate cortisol and ACTH release in patients with Cushing's disease: comparison with DDAVP	Oliveira JH et al.	Journal of endocrinological investigation	2003	Randomized Controlled Trial
GH-releasing peptide (GHRP-6)-induced ACTH release in patients with addison's disease: effect of glucocorticoid withdrawal	Martins MR et al.	Journal of endocrinological investigation	2003	Clinical Trial
Effects of growth hormone-releasing peptides in healthy dogs and in dogs with pituitary-dependent hyperadrenocorticism	Bhatti SF et al.	Molecular and cellular endocrinology	2002	Randomized Controlled Trial
Physical activity or food intake prior to testing did not affect the reproducibility of GH secretion elicited by GH releasing hormone plus GH-releasing hexapeptide in normal adult subjects	Popovic V et al.	Clinical endocrinology	2002	Clinical Trial
Effects of fasting and pegvisomant on the GH-releasing hormone and GH-releasing peptide-6 stimulated growth hormone secretion	Muller AF et al.	Clinical endocrinology	2001	Randomized Controlled Trial
GH-releasing hormone and GH-releasing peptide-6 for diagnostic testing in GH-deficient adults	Popovic V et al.	Lancet (London, England)	2000	Clinical Trial
Effects of short-term glucocorticoid deprivation on growth hormone (GH) response to GH-releasing peptide-6: studies in normal men and in patients with adrenal insufficiency	Pinto AC et al.	The Journal of clinical endocrinology and metabolism	2000	Controlled Clinical Trial
Acute dexamethasone administration enhances GH responsiveness to GH releasing peptide-6 (GHRP-6) in man	Pinto AC et al.	Clinical endocrinology	1999	Randomized Controlled Trial
Effects of growth hormone-releasing peptide-6 on the nocturnal secretion of GH, ACTH and cortisol and on the sleep EEG in man: role of routes of administration	Frieboes RM et al.	Journal of neuroendocrinology	1999	Clinical Trial
Growth hormone (GH) response to GH-releasing peptide-6 and GH-releasing hormone in normal-weight and overweight patients with non-insulin-dependent diabetes mellitus	Micić D et al.	Metabolism: clinical and experimental	1999	Randomized Controlled Trial
Tyr-Ala-Hexarelin, a synthetic octapeptide, possesses the same endocrine activities of Hexarelin and GHRP-2 in humans	Arvat E et al.	Journal of endocrinological investigation	1999	Randomized Controlled Trial
Preserved growth hormone (GH) secretion in aged and very old subjects after testing with the combined stimulus GH-releasing hormone plus GH-releasing hexapeptide-6	Micic D et al.	The Journal of clinical endocrinology and metabolism	1998	Controlled Clinical Trial
Growth hormone (GH)-releasing peptide-6 requires endogenous hypothalamic GH-releasing hormone for maximal GH stimulation	Pandya N et al.	The Journal of clinical endocrinology and metabolism	1998	Randomized Controlled Trial
Different effects of growth hormone releasing peptide (GHRP-6) and GH-releasing hormone on GH release in endogenous and exogenous hypercortisolism	Borges MH et al.	Clinical endocrinology	1997	Randomized Controlled Trial

More cited research

Conditions researched

Related compounds

FAQ

What is GHRP-6?

An early synthetic hexapeptide ghrelin-receptor agonist that releases growth hormone and strongly increases appetite.

How many registered human trials study GHRP-6?

The PeptideWhiz trial index lists 0 registered trials for GHRP-6.

How much published research exists on GHRP-6?

The PeptideWhiz paper index links 45 PubMed papers to GHRP-6; by study type, 178 human and 387 animal studies.

Which conditions is GHRP-6 researched for?

Anti-aging & longevity, Concussion, traumatic brain injury & stroke recovery, Fat loss, obesity & body recomposition, Insulin resistance, prediabetes & type 2 diabetes, PCOS, Sleep problems (incl. insomnia on peptides), Thyroid problems.

Research and education only. Not medical advice. No dosing guidance. Data: ClinicalTrials.gov registry and PubMed via the PeptideWhiz index (204,289 studies).

Reported dosing ranges from research