GHRP-6
First-generation GH secretagogue; strongly stimulates appetite via ghrelin pathway.
🔬 Mechanism of Action
GHRP-6 is a first-generation hexapeptide growth hormone releasing peptide that activates the ghrelin receptor (GHS-R1a) on pituitary somatotroph cells. It produces a strong, dose-dependent GH release pulse. Unlike Ipamorelin, GHRP-6 is non-selective — it also significantly stimulates appetite via the ghrelin pathway, elevates cortisol, and increases prolactin.
The appetite-stimulating effect is pronounced and is considered either a benefit or drawback depending on the user's goals. For individuals seeking to increase caloric intake (e.g., recovery from illness or muscle building), this is advantageous.
Source: PMID: 9003422
📜Background & History
GHRP-6 (Growth Hormone Releasing Hexapeptide-6) was the first synthetic GHRP discovered, developed by Cyril Bowers at Tulane University in 1984. It was the compound that revealed the existence of a distinct ghrelin receptor (GHS-R1a) separate from the GHRH receptor — a foundational discovery in endocrinology. The strong appetite stimulation it produces (via central ghrelin mimicry) was initially considered a side effect but has since been recognized as a feature for cachexia and underweight conditions.
🎯 Research Use Cases
- ✓Bulking protocols where appetite stimulation is desired
- ✓Cachexia management: cancer, HIV, or chronic illness-related muscle wasting
- ✓GH stimulation in combination with GHRH analogs
- ✓Gastroprotective effects noted in some animal models (similar to BPC-157)
💉 Dosing Protocol
| Typical Dose | 100-300 mcg/injection |
| Frequency | 2-3× daily |
| Half-Life | 15-60 minutes |
| Common Vial Sizes | 5 mg |
🧪 Reconstitution Example
⚠️Safety & Considerations
Research peptide. Strongly stimulates appetite — be aware of this if weight management is a goal. May elevate cortisol and prolactin temporarily. Use on an empty stomach.
⚡Interactions & Contraindications
Diabetes/insulin resistance: appetite stimulation can make caloric control difficult. Elevated cortisol with chronic use may affect adrenal function and immune status. Strong hunger response within 20 minutes of injection — plan food availability.
🔗Synergies & Common Stacks
GHRH+GHRP synergy: powerful GH output for anabolic and recovery goals. More total GH release than with Ipamorelin but with cortisol/appetite side effects.
Emerging research suggests GHRP-6 and BPC-157 share gastroprotective pathways. May complement each other for GI healing protocols.
