Overview
GHRP-6 (Growth Hormone Releasing Peptide-6) is a synthetic hexapeptide (6 amino acids) and one of the earliest growth hormone secretagogues developed. First synthesized in the 1980s, it stimulates growth hormone release from the pituitary gland by activating the ghrelin receptor. While effective, its broader hormonal effects make it less selective than newer alternatives like Ipamorelin.
Mechanism of Action
GHRP-6 stimulates GH release through multiple pathways:
- Ghrelin receptor activation (GHS-R1a) in the pituitary gland
- Suppression of somatostatin — the hormone that inhibits GH release
- Amplification of GHRH signaling — works synergistically with the body's own growth hormone releasing hormone
- Direct pituitary stimulation — bypasses the hypothalamus for a portion of its effect
Unlike Ipamorelin, GHRP-6 also significantly stimulates:
- Appetite through ghrelin pathway activation (this is the main differentiator)
- Cortisol release (moderate increase)
- Prolactin release (mild-moderate increase)
Research Applications
Growth Hormone Deficiency
- GHRP-6 produces robust, dose-dependent GH release
- Has been studied as a diagnostic tool for GH deficiency
- Shows consistent GH elevation even in older subjects with age-related decline
Appetite Stimulation
- The strong appetite-stimulating effect makes GHRP-6 of interest for:
- Cachexia (wasting syndrome) in cancer and HIV/AIDS
- Anorexia recovery
- Failure to thrive in elderly populations
Cardioprotection
- Interesting preclinical data showing potential protective effects on cardiac tissue
- Studies in rats demonstrate reduced infarct size following induced heart attacks
- May protect against ischemia-reperfusion injury
Gastroprotection
- Some evidence of protective effects on the gastric mucosa
- May complement other peptides' gut-healing properties
Dosage Information
Note: No FDA-approved dosing guidelines exist. Based on research:
- Common research dose: 100-300 mcg per administration
- Frequency: 2-3 times daily
- Route: Subcutaneous injection
- Timing: On an empty stomach (30+ minutes before eating)
- Important note: The intense appetite spike typically occurs 20-30 minutes post-injection
Safety Profile
Commonly reported:
- Intense hunger — often dramatic, onset within 20 minutes
- Injection site irritation
- Water retention
- Cortisol elevation
- Tingling/numbness in extremities
- Mild dizziness
Less common:
- Elevated prolactin with chronic use
- Blood sugar fluctuations
- Joint stiffness from water retention
GHRP-6 vs Newer Alternatives
GHRP-6 is largely considered outdated by the research community due to its lack of selectivity. However, the appetite stimulation remains uniquely useful for specific applications.
| Feature | GHRP-6 | Ipamorelin | CJC-1295 | | --- | --- | --- | --- | | Type | GHRP | GHRP | GHRH analog | | GH release | Strong | Moderate | Moderate | | Appetite | Very strong | None | None | | Cortisol | Elevated | Minimal | None | | Best for | Appetite + GH | Clean GH release | Extended GH elevation |
Research Status
- FDA Status: Not FDA-approved for any indication
- Clinical Data: Extensive preclinical data; limited human trial data
- Legal Status: Available for research purposes in most jurisdictions
Profile last updated: January 2026