NO. 034 · STAGE 1 · Lv. 70 · HP 125
GHRP-6
High-Appetite Ghrelin Receptor Agonist
ALIASES
GHRP-6, growth hormone-releasing peptide 6, His-D-Trp-Ala-Trp-D-Phe-Lys
CLASS
Synthetic hexapeptide · ghrelin receptor agonist (high appetite signal)
FORMULA
C46H56N12O6
SEQUENCE
His-D-Trp-Ala-Trp-D-Phe-Lys-NH2
HALF-LIFE
~15-60 minutes
ROUTES
Subcutaneous (research)
MECHANISM OF ACTION
Hexapeptide ghrelin receptor (GHS-R1a) agonist. Drives pituitary GH release with the strongest concomitant hunger signal in the GHRP class via direct ghrelin-mimetic activity on the arcuate nucleus.
EVIDENCE GRADES
Well-characterized GHS-R1a binding (Bowers 1991). The historic prototype that established the GH-releasing peptide class.
Strongest appetite signal in the GHRP class via direct ghrelin-mimetic activity on arcuate nucleus neurons.
No completed long-term Phase 3 trials.
MECHANISM CATEGORIES
RESEARCH CONDITIONS
SAFETY
Side effects
- Strong appetite stimulation
- Mild cortisol elevation
- Mild prolactin elevation
- Flushing
- Injection-site reactions
Known interactions
- Concurrent rhGH not recommended
- Glucocorticoids may blunt response
Contraindications
- Active malignancy
- Pituitary tumor
- Pregnancy/lactation
REGULATORY STATUS
FDA · Not FDA-approved. Research-use only.
WADA · Prohibited at all times under WADA Section S2 (growth-hormone-secretagogue sub-category).
STORAGE
Lyophilized · 4 °C 24 months
Reconstituted · 2-8 °C, 28 days
PEER-REVIEWED EVIDENCE
- Bowers CY, Momany FA, Reynolds GA, Hong A. On the in vitro and in vivo activity of a new synthetic hexapeptide that acts on the pituitary to specifically release growth hormone. Endocrinology 1984. link →
- Smith RG, Van der Ploeg LH, Howard AD, et al.. Peptidomimetic regulation of growth hormone secretion. Endocr Rev 1997. link →
FAQ · 8 QUESTIONS
▶ What is GHRP-6?
GHRP-6 is a synthetic hexapeptide ghrelin / GHS-R1a receptor agonist · the historic prototype that established the GH-releasing peptide class. Bowers 1991 first characterized its GH-releasing activity. Strongest appetite stimulation in the GHRP class.
▶ GHRP-6 vs GHRP-2 · what's the difference?
Both are hexapeptide ghrelin receptor agonists. GHRP-6 has the strongest appetite signal in the GHRP class via direct ghrelin-mimetic activity. GHRP-2 has lower appetite signal due to differential downstream signaling. Both produce mild cortisol and prolactin elevation alongside the GH pulse.
▶ GHRP-6 vs ipamorelin · which is better?
Ipamorelin is selective (no significant cortisol/prolactin/appetite elevation). GHRP-6 is non-selective with stronger appetite signal and mild stress-hormone elevation. Ipamorelin has the cleaner profile; GHRP-6 is preferred only when appetite stimulation is part of the research design.
▶ Why does GHRP-6 cause hunger?
GHRP-6 is a direct ghrelin mimetic at the GHS-R1a receptor on arcuate-nucleus AgRP/NPY neurons. Activation of these neurons drives appetite stimulation as the canonical downstream effect of ghrelin signaling. Newer GHS like ipamorelin engage GHS-R1a with biased signaling that minimizes the appetite arm.
▶ Is GHRP-6 FDA-approved?
No. Research-use only.
▶ Is GHRP-6 WADA-prohibited?
Yes. GHRP-6 is prohibited at all times under WADA Section S2 in the growth-hormone-secretagogue sub-category.
▶ What is the half-life of GHRP-6?
Approximately 15-60 minutes plasma half-life. Multiple daily administrations are needed for sustained GH-axis stimulation in research protocols.
▶ How is GHRP-6 paired with a GHRH analog?
GHRP-6 + CJC-1295 No DAC engages both upstream regulators of GH release. The two pathways are independent and complementary; combined activation amplifies the GH pulse synergistically. Less commonly used than ipamorelin + CJC-1295 due to GHRP-6's appetite and stress-hormone side effects.
SIGNATURE MOVES
Strongest appetite stimulation in the GHRP class.
Pulsatile GH release. Often paired with a GHRH analog.
SOURCED FROM PEPPU LABS
Reference compounds documented on this page are available as research-grade material at Peppu Studio · ≥99% purity · per-batch Certificate of Analysis. For laboratory research use only. No human dose is recommended by this wiki.
▶ LAST UPDATED · 2026-05-25