GHRP-6
Grade B: Human evidence, not approved for this use
Key Takeaways
- Grade B: Human evidence, not approved for this use
- Not FDA approved: Not FDA-approved for any indication; classified by FDA as a bulk drug substance with significant safety concerns (Category 2), prohibited from compounding for human use as of June 2026.
- Compounding: The FDA placed GHRP-6 in Category 2 of its interim 503A/503B bulk-substances policy, the list of substances it has identified as presenting potential significant safety risks, so it is not eligible for routine pharmacy compounding.
Mechanism
GHRP-6 binds the ghrelin receptor (GHSR-1a) on pituitary somatotrophs, stimulating GH release through a pathway distinct from GHRH; it also activates hypothalamic and peripheral ghrelin receptors, directly driving the potent appetite-stimulating effect.
Evidence
GHRP-6 (growth hormone-releasing hexapeptide-6) is a synthetic hexapeptide ghrelin mimetic that stimulates GH secretion through the ghrelin receptor (GHSR-1a). Published human evidence consists primarily of pharmacodynamic and diagnostic studies: GHRP-6 has been used as a provocative stimulation test for GH deficiency in endocrinology, and its GH-secreting effects in humans are well-documented in this context (PMID 9156038 and related diagnostic studies). However, these are physiological characterization studies, not therapeutic efficacy trials for any clinical indication. Preclinical studies in organ-injury models (acute kidney injury, doxorubicin cardiotoxicity, lung injury) are published, but none of this animal data has been translated into published human therapeutic RCTs. GHRP-6 produces the strongest appetite stimulation of any peptide in the GHRP class, a pharmacological effect that is well-documented in human studies. The Grade B designation reflects confirmed human pharmacodynamic data, not proven therapeutic efficacy.
Safety and risks
GHRP-6 is not FDA-approved for any human therapeutic use and the FDA has classified it as a substance presenting significant safety concerns for compounding. The most clinically prominent safety issue is intense and pronounced appetite stimulation: GHRP-6 produces the strongest ghrelin-mediated hunger response in its class, typically within 20 minutes of injection, which is particularly problematic if used in weight-management contexts or in patients with eating disorders. Cortisol and prolactin elevation is documented in human studies at standard doses; sustained cortisol elevation can adversely affect glucose regulation, sleep architecture, mood, and immune function. Chronic IGF-1 elevation from sustained GH stimulation raises the same theoretical proliferative risk described for CJC-1295 (IGF-1 as a mitogenic, anti-apoptotic factor). GHRP-6 is prohibited in all competitive sports by WADA. Long-term human safety data are absent. The compound is banned from compounding under FDA safety-concern classification and should be considered research-use-only in the US context.
Interactions
Additive GH/IGF-1 effects when combined with GHRH analogs (e.g., CJC-1295); may compound insulin-sensitizing or insulin-desensitizing effects of antidiabetic agents; elevated cortisol from GHRP-6 may blunt the efficacy of exogenous glucocorticoids or interact with HPA-axis medications.
Federal compounding status
503A/503B Category 2: significant safety risk as of 2023.
The FDA placed this substance (503B) in Category 2 of its interim bulk-substances policy, the list it has identified as presenting potential significant safety risks, so it is not eligible for routine pharmacy compounding. FDA source
Federal status only, from public FDA records. State pharmacy-board rules vary and are not covered here. This is regulatory reporting, not legal advice. All compounds.
Compounding legality
The FDA placed GHRP-6 in Category 2 of its interim 503A/503B bulk-substances policy, the list of substances it has identified as presenting potential significant safety risks, so it is not eligible for routine pharmacy compounding.
Sources
- Growth hormone releasing hexapeptide-6 (GHRP-6) test in the diagnosis of GH-deficiency. (1996) review
- Growth hormone-releasing peptide 6 (GHRP-6) hydrogel for acute kidney injury therapy via metabolic regulation. (2025) other
- Growth hormone releasing peptide-6 (GHRP-6) prevents doxorubicin-induced myocardial and extra-myocardial damages by activating prosurvival mechanisms. (2024) other
- Regulation of growth hormone secretion by the growth hormone releasing hexapeptide (GHRP-6). (1993) review
- Growth hormone responses to GH-releasing peptide (GHRP-6) in hypothyroidism. (1997) rct
- GHRP-6 induces CREB phosphorylation and growth hormone secretion via a protein kinase Csigma-dependent pathway in GH3 cells. (2010) other
- Diagnosis of growth hormone deficiency in adults by testing with GHRP-6 alone or in combination with GHRH: comparison with the insulin tolerance test. (2002) other
- Growth hormone response to GHRH, GHRP-6 and GHRH + GHRP-6 in patients with polycystic ovary syndrome. (1996) other
- Use of growth-hormone-releasing peptide-6 (GHRP-6) for the prevention of multiple organ failure. (2006) other
- Growth hormone releasing peptide-6 (GHRP-6) ameliorates acute lung injury and its subsequent evolvement to interstitial fibrosis. (2026) other
- Growth hormone releasing hexapeptide (GHRP-6) activates the inositol (1,4,5)-trisphosphate/diacylglycerol pathway in rat anterior pituitary cells. (1995) other
- Growth hormone secretion after the administration of GHRP-6 or GHRH combined with GHRP-6 does not decline in late adulthood. (1995) rct
- Growth hormone response to GHRH + GHRP-6 in type 2 diabetes during euglycemic and hyperglycemic clamp. (2004) other
- Pharmacokinetic study of Growth Hormone-Releasing Peptide 6 (GHRP-6) in nine male healthy volunteers. (2013) rct
- Growth hormone secretion elicited by GHRH, GHRP-6 or GHRH plus GHRP-6 in patients with microprolactinoma and macroprolactinoma before and after bromocriptine therapy. (1998) other
- Growth hormone releasing peptide (GHRP-6) stimulates phosphatidylinositol (PI) turnover in human pituitary somatotroph cells. (1995) other
- Influence of sex, age and adrenergic pathways on the growth hormone response to GHRP-6. (1993) other
- Blocked growth hormone-releasing peptide (GHRP-6)-induced GH secretion and absence of the synergic action of GHRP-6 plus GH-releasing hormone in patients with hypothalamopituitary disconnection: evidence that GHRP-6 main action is exerted at the hypothalamic level. (1995) other
- Different effects of growth hormone releasing peptide (GHRP-6) and GH-releasing hormone on GH release in endogenous and exogenous hypercortisolism. (1997) rct
- Determination of growth hormone releasing peptides metabolites in human urine after nasal administration of GHRP-1, GHRP-2, GHRP-6, Hexarelin, and Ipamorelin. (2015) other
- Pituitary enlargement due to primary hypothyroidism: growth hormone response to GHRH, GHRP-6 and GHRH plus GHRP-6. (1996) observational
- Growth hormone releasing peptides: a comparison of the growth hormone releasing activities of GHRP-2 and GHRP-6 in rat primary pituitary cells. (1997) other
- Effect of growth hormone (GH)-releasing hormone (GHRH), atropine, pyridostigmine, or hypoglycemia on GHRP-6-induced GH secretion in man. (1993) other
- Effect of obesity and morbid obesity on the growth hormone (GH) secretion elicited by the combined GHRH + GHRP-6 test. (2006) other
- Central effects of growth hormone-releasing hexapeptide (GHRP-6) on growth hormone release are inhibited by central somatostatin action. (1995) other
GHRP-6 is Not FDA approved. PeptideGrids presents evidence and regulatory status for informational purposes only. We do not sell, supply, source, or help anyone obtain this compound, and we provide no dosing or administration guidance. This is not medical advice; consult a licensed clinician. Full disclaimer.
Last reviewed June 1, 2026 by PeptideGrids editorial team (independently audited).