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GHRP-6

unknown risk

Also: Growth Hormone Releasing Peptide-6 · His-DTrp-Ala-Trp-DPhe-Lys-NH2

Preliminary Research Only

GHRP-6 is a synthetic hexapeptide GH secretagogue notable for strong appetite stimulation via ghrelin pathway activation. It was one of the first characterized GHRPs and remains used in cachexia and wasting research.

Molecular Weight
873.0 g/mol
Formula
C46H56N12O6
Common Dosing
100-300 mcg 2-3x daily subcutaneous
Category
research
Last Reviewed
2025-01-15

Reported Benefits

GH Release

Preliminary 18 studies

Reliable GH secretion demonstrated in human studies.

Appetite Stimulation

Preliminary 12 studies

Pronounced hunger increase — useful for cachexia, problematic for weight management.

Cardioprotection

Preliminary 6 studies

Similar CD36-mediated cardiac effects as hexarelin in animal models.

Mechanism of Action

GHRP-6 binds GHSR-1a ghrelin receptors, triggering GH release and appetite stimulation simultaneously. The appetite effect is more pronounced than GHRP-2 or ipamorelin. Also has some cortisol/prolactin-stimulating activity.

Key Clinical Studies

Bowers CY (1993)

pharmacodynamic · Healthy adults

GH release with significant appetite stimulation effect

Overview

GHRP-6 is the original growth hormone releasing peptide, discovered before GHRP-2 and ipamorelin. Its strong appetite-stimulating effect — a direct result of ghrelin receptor activation — makes it particularly relevant for cachexia and muscle-wasting conditions where both GH secretion and appetite increase are desired.

Appetite as Feature and Bug

The pronounced appetite stimulation that limits GHRP-6 utility in weight management protocols becomes therapeutically relevant in cancer cachexia, HIV wasting syndrome, and post-surgical recovery where improving nutritional intake is a priority. This characteristic differentiates its clinical niche from ipamorelin.

Historical Significance

GHRP-6 was instrumental in characterizing the ghrelin receptor system before ghrelin itself was discovered. The discovery that a synthetic peptide could activate what was later identified as the ghrelin receptor opened an entire field of metabolic and appetite research.

Current Use Context

In clinical anti-aging practice, GHRP-6 has largely been supplanted by ipamorelin due to ipamorelin’s cleaner cortisol/prolactin profile. GHRP-6 retains relevance in research contexts and in specific clinical scenarios where appetite stimulation is desired.

Regulatory Status

Research Only

Not FDA-approved; research-only status

Safety Profile

Side Effects

  • Significant appetite increase
  • Water retention
  • Cortisol elevation
  • Prolactin elevation

Contraindications

  • Active malignancy
  • Diabetes
  • Obesity

Drug Interactions

  • Insulin
  • Glucocorticoids

Primary Uses

GH secretagogueMuscle buildingAppetite stimulationAnti-catabolism

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Disclaimer: This information is for educational and research purposes only. Not medical advice. Consult a qualified healthcare provider before using any compound.