Ipamorelin vs GHRP-2
Side-by-Side Comparison
| Attribute | Ipamorelin | Ghrp 2 |
|---|---|---|
| Category | Growth Hormone Secretagogue | Growth Hormone Secretagogue |
| Mechanism | Ipamorelin (sequence: Aib-His-D-2Nal-D-Phe-Lys-NH2) selectively binds to the Growth Hormone Secretagogue Receptor (GHS-R1a) on anterior pituitary somatotroph cells, increasing cAMP and activating... | GHRP-2 (C45H55N9O6) binds to and activates ghrelin (GH secretagogue) receptors on pituitary somatotrophs, triggering robust pulsatile GH release. |
| Evidence Rating | D — Preclinical | C — Phase I–II Clinical Trials |
| Clinical Status | Research-only / Not approved for human use | Approved in Japan for GH deficiency diagnosis; research-only elsewhere |
| Safety Profile | Widely regarded as the mildest GHS available; minimal side effects in published animal and human studies; Common: injection site reactions (redness, swelling, bruising) in 15-30% of users, resolving within 24-48 hours | Well tolerated in clinical trials with placebo-like safety profile at therapeutic ranges; May increase appetite (less than GHRP-6) |
| Route | Subcutaneous | Subcutaneous |
| Dose Range | 100–300 mcg per injection, 2–3x daily | 100–300 mcg per injection, 2–3x daily |
| Frequency | 2–3 times daily (typically before meals and before bed) | 2–3 times daily |
| Molecular Weight | ~711.9 g/mol | ~817.0 g/mol |
| Half-Life | ~2 hours | ~15–60 minutes |
Overview
Ipamorelin and GHRP-2 are both research peptides studied across multiple applications. This comparison examines their mechanisms, evidence base, dosing protocols, and safety profiles to help researchers understand the key differences and overlaps.
Ipamorelin — Mechanism & Evidence
Ipamorelin is the most selective growth hormone secretagogue (GHS) available, a synthetic pentapeptide (MW ~711.86 g/mol, formula C38H49N9O5) that stimulates pulsatile GH release from the pituitary gland without significantly affecting cortisol, prolactin, or appetite. It is widely regarded as the mildest GHS, making it popular in anti-aging, body composition, and recovery contexts. However, research on ipamorelin is limited, and it is not FDA-approved for any indication.
Key claims: Increases growth hormone levels; Improves body composition; Improves sleep quality.
GHRP-2 — Mechanism & Evidence
GHRP-2 (pralmorelin) is a synthetic hexapeptide growth hormone secretagogue (D-Ala-D-2-Nal-Ala-Trp-D-Phe-Lys-NH2, MW ~817.97 g/mol) that stimulates potent, dose-dependent GH release via the ghrelin receptor (GHS-R). It is considered more potent than GHRP-6 with less appetite stimulation. Approved in Japan as a diagnostic agent for GH deficiency (pralmorelin), it has been used clinically in GH-deficient children for 8-24 months with maintained efficacy on growth velocity. Clinical studies show a placebo-like safety profile at therapeutic doses.
Key claims: Potent growth hormone release; Diagnostic tool for GH deficiency; Sustained efficacy in long-term use.
Shared Research Applications
Both peptides are studied for: Body Composition.
Ipamorelin is also researched for: Anti-Aging, Sleep.
GHRP-2 is also researched for: no additional unique applications.
Safety Considerations
Ipamorelin: Widely regarded as the mildest GHS available; minimal side effects in published animal and human studies Common: injection site reactions (redness, swelling, bruising) in 15-30% of users, resolving within 24-48 hours Common: mild temporary "head rush" or flushing immediately after injection due to sudden vasodilation
GHRP-2: Well tolerated in clinical trials with placebo-like safety profile at therapeutic ranges May increase appetite (less than GHRP-6) Can elevate cortisol and prolactin levels (less than GHRP-6)
Related Products
Related Research News
Ipamorelin vs GHRP-2: Which Offers More Targeted GH Release?
Ipamorelin and GHRP-2 both stimulate growth hormone release via the ghrelin receptor, but Ipamorelin provides more selective action with minimal impact on other hormones like ACTH and cortisol. GHRP-2 delivers stronger GH pulses alongside broader endocrine effects. Combining them can enhance overall GH output through additive receptor stimulation.
CJC-1295 with DAC and Ipamorelin: Growth Hormone Research Guide
CJC-1295 with DAC and Ipamorelin represent key compounds in growth hormone research, targeting distinct pathways for GH and IGF-1 signaling. CJC-1295 with DAC acts as a long-acting GHRH analogue with a half-life of 5.8 to 8.1 days, while Ipamorelin functions as a selective growth hormone secretagogue via the ghrelin receptor. Together, they support studies on metabolism, recovery, and body composition.
Ipamorelin: Selective GH Secretagogue for Clean Pulsatile Release
Ipamorelin, a third-generation GHS-R1a agonist (CAS 170851-70-4), stimulates pulsatile growth hormone release without elevating cortisol or prolactin, unlike earlier GHRPs. This selectivity supports precise research into GH axis effects, IGF-1 pathways, body composition, recovery, and sleep. Studies highlight its role in anabolic processes and synergy with CJC-1295 for enhanced GH output.

