Ipamorelin vs GHRP-6
Two popular growth hormone secretagogues compared for selectivity and side effects
Ipamorelin and GHRP-6 are both growth hormone secretagogues (GHRPs) that stimulate GH release through the ghrelin receptor. The key differentiator is selectivity: Ipamorelin is one of the most selective GHRPs, stimulating GH release with minimal effects on cortisol, prolactin, or appetite. GHRP-6 is more potent but less selective, producing notable hunger stimulation and modest cortisol/prolactin elevation.
This selectivity tradeoff makes Ipamorelin the go-to recommendation for researchers new to GH peptides, while GHRP-6 appeals to those prioritizing maximal GH output or appetite stimulation.
Head-to-Head Comparison
| Dimension | Ipamorelin | GHRP-6 |
|---|---|---|
| Selectivity | Highly selective for GH release | Less selective — affects multiple hormones |
| GH Release Potency | Moderate GH elevation | Strong GH elevation |
| Cortisol Effect | No significant increase | Mild increase at higher doses |
| Prolactin Effect | No significant increase | Mild increase |
| Hunger Stimulation | Minimal to none | Strong — significant appetite increase |
| Side Effects | Minimal (occasional head rush) | Intense hunger, water retention, cortisol elevation |
| Beginner Friendly | Yes — clean side effect profile | Moderate — hunger and hormonal effects may be unwanted |
Ipamorelin
Ipamorelin is a selective compound that triggers growth hormone release, originally developed by Novo Nordisk. It stimulates growth hormone without significantly affecting cortisol or prolactin levels. It has been studied in clinical trials for postoperative recovery.
GHRP-6
GHRP-6 (Growth Hormone Releasing Peptide-6) is a six-amino-acid peptide that triggers growth hormone release through the ghrelin (hunger hormone) receptor. It is known for strong growth hormone release but also significant appetite stimulation.
Can You Stack Ipamorelin and GHRP-6?
Ipamorelin and GHRP-6 can technically be stacked, but it's generally considered redundant since both act on the ghrelin receptor. The standard approach is to choose one GHRP and pair it with a GHRH analog (like CJC-1295 or Sermorelin) for synergistic GH release through complementary receptor pathways.
Frequently Asked Questions
Which is better for beginners — Ipamorelin or GHRP-6?
Ipamorelin is widely considered the better choice for beginners. Its high selectivity means it stimulates GH release without significantly affecting cortisol, prolactin, or appetite. GHRP-6's strong hunger stimulation and broader hormonal effects make it less predictable for those new to GH peptides.
Does GHRP-6 make you hungry?
Yes, GHRP-6 is well-known for causing significant appetite stimulation — often within 20-30 minutes of injection. This is due to its activation of ghrelin receptors, which play a central role in hunger signaling. This effect can be beneficial for those trying to increase caloric intake but is a drawback for others.
Which raises growth hormone more — Ipamorelin or GHRP-6?
GHRP-6 generally produces a larger acute GH spike than Ipamorelin. However, this comes with less selectivity — GHRP-6 also raises cortisol and prolactin to some degree. Ipamorelin's GH elevation, while slightly lower in peak amplitude, is considered "cleaner" with fewer off-target hormonal effects.