Source comparison
Peptides for Growth Hormone Deficiency: Mechanism Comparison
GHRH Analogs (CJC-1295, Sermorelin) GHRH receptor on pituitary somatotrophs Activates adenylyl cyclase → increases cAMP → opens calcium channels → GH granule release Amplifies natural pulse amplitude without changing frequency CJC-1295: 6–8 days; Sermorelin: 8
This comparison does not assign a generated winner or score.
- GHRH Analogs (CJC-1295, Sermorelin)
- GHRH receptor on pituitary somatotrophs
- Activates adenylyl cyclase → increases cAMP → opens calcium channels → GH granule release
- Amplifies natural pulse amplitude without changing frequency
- CJC-1295: 6–8 days; Sermorelin: 8–12 minutes
- High synergy with ghrelin mimetics (independent pathways)
- Ghrelin Mimetics (Ipamorelin, GHRP-2, Hexarelin)
- GHS-R1a (ghrelin receptor) on pituitary
- Triggers GH release through pathway independent of GHRH signaling
- Increases pulse frequency and sharpens peak height
- 2–3 hours
- High synergy with GHRH analogs (separate receptor activation)
- Synthetic HGH
- IGF-1 receptor (peripheral) and GH receptor (hepatic)
- Direct hormone replacement. Bypasses pituitary entirely
- Flattens natural pulse pattern through negative feedback on GHRH
- 3–4 hours (subcutaneous)
- No synergy. Suppresses endogenous pathways
- MK-677 (Ibutamoren)
- GHS-R1a (oral ghrelin mimetic)
- Oral bioavailability; triggers GH release through ghrelin receptor
- Increases baseline GH and pulse frequency moderately
- 24 hours
- Moderate synergy with GHRH analogs but increases appetite significantly
- Professional Assessment
- The combination of GHRH analogs + ghrelin mimetics restores physiological GH dynamics that synthetic HGH cannot replicate. Preserving pulsatile secretion prevents receptor desensitization and maintains long-term efficacy without cycling requirements.