GHRP-2 vs Sermorelin
GHRP-2 (Growth-hormone secretagogue (GHRP) / ghrelin receptor agonist) and Sermorelin (GHRH analog (growth-hormone-releasing hormone analog)) are documented as co-studied in the PeptiDex library. This page puts the two entries side by side on class, molecular weight, half-life, origin, mechanism and studied research areas — every value taken from the entry it belongs to.
Why these two are co-studied
Cross-referenced for research context — not a usage or combination recommendation.
At a glance
| Attribute | GHRP-2 | Sermorelin |
|---|---|---|
| Compound class | Growth-hormone secretagogue (GHRP) / ghrelin receptor agonist | GHRH analog (growth-hormone-releasing hormone analog) |
| Research category | Growth & GH-Axis | Growth & GH-Axis |
| Length (amino acids) | 6 amino acids | 29 amino acids |
| Molecular weight | 817.0 g/mol | 3357.9 g/mol |
| Half-life | Short, on the order of tens of minutes (reported approximately 30-60 minutes) | Short, on the order of minutes (reported approximately 10-20 minutes) |
| Origin | GHRP-2 (pralmorelin) is a synthetic hexapeptide growth-hormone secretagogue. It has been used in Japan as a diagnostic agent for assessing growth-hormone secretory capacity. | Sermorelin is a synthetic peptide corresponding to the first 29 amino acids of human growth-hormone-releasing hormone (GHRH 1-29), the shortest fully active fragment of GHRH. It was formerly marketed as Geref. |
“Not documented” means the PeptiDex entry records no value for that field. Nothing on this page is estimated, and no figure is carried over from one compound to the other.
How GHRP-2 works
GHRP-2 is an agonist of the growth-hormone secretagogue receptor (GHS-R1a, ghrelin receptor), stimulating pulsatile GH release from the pituitary. It is a potent GH secretagogue and also stimulates appetite via ghrelin-receptor signaling. It can modestly increase ACTH, cortisol, and prolactin, though generally less than GHRP-6 for appetite effects.
How Sermorelin works
Sermorelin is an agonist of the GHRH receptor on anterior-pituitary somatotrophs, stimulating the synthesis and pulsatile secretion of endogenous growth hormone. Because it acts upstream and preserves physiologic feedback, GH release remains subject to somatostatin regulation. Its effect on the GH/IGF-1 axis is thereby more physiologic than direct GH administration.
Mechanistic descriptions reflect published research-literature understanding and are quoted from each compound's own entry. Much peptide research is preclinical (in-vitro or animal-model); mechanism in humans may differ and is not established for many compounds.
Where each one appears in the literature
The research contexts each entry documents. Listing a research area is not a claim of efficacy or a therapeutic indication, and the two lists are not scored against each other.
GHRP-2
Sermorelin
What sets each apart
GHRP-2
GHRP-2 is a potent GH releaser with an approved diagnostic use in Japan (pralmorelin), and it stimulates appetite, distinguishing it from the more selective ipamorelin.
Sermorelin
Sermorelin is a GHRH-receptor agonist (GHRH 1-29) rather than a ghrelin-receptor GHRP, and it is shorter-acting than modified GHRH analogs such as CJC-1295 or tesamorelin.
Frequently asked questions
Why is GHRP-2 studied with a GHRH analog?
GHRP-2 stimulates the ghrelin receptor while GHRH analogs (CJC-1295, sermorelin) stimulate the GHRH receptor. Combining the two produces a synergistic GH pulse larger than either pathway alone, a widely referenced approach in GH-secretagogue research.
What is GHRP-2 (pralmorelin)?
GHRP-2, also called pralmorelin, is a synthetic hexapeptide growth hormone-releasing peptide that activates the ghrelin receptor (GHS-R1a) to stimulate pulsatile GH secretion from the anterior pituitary. It is one of the most clinically studied GHRPs and was developed as a diagnostic agent for GH deficiency.
How does GHRP-2 differ from ipamorelin?
Both activate the ghrelin receptor, but GHRP-2 is a stronger GH stimulus that also produces more transient elevation of cortisol and prolactin, whereas ipamorelin is more selective with minimal effect on those hormones. Research design often chooses between them based on whether off-target hormone effects are acceptable.
Why is sermorelin often studied with a GHRP?
Sermorelin acts on the GHRH receptor while GHRPs like ipamorelin or GHRP-2 act on the ghrelin receptor. Research pairing the two exploits the two complementary pathways to produce a larger, synergistic GH pulse than either alone.
What is sermorelin?
Sermorelin is a synthetic 29-amino-acid peptide corresponding to the biologically active amino-terminal fragment (residues 1-29) of human growth hormone-releasing hormone (GHRH). It binds the GHRH receptor on the anterior pituitary and is studied for its ability to stimulate the body's own GH production.
How does sermorelin differ from CJC-1295?
Both are GHRH analogs based on the GRF(1-29) sequence, but sermorelin is the unmodified fragment with a very short (~11-12 minute) half-life, whereas CJC-1295 adds amino-acid substitutions (and, in the DAC version, albumin binding) to resist enzymatic breakdown and extend duration substantially.
Answers are the ones published on each compound's own PeptiDex entry. They are educational summaries of research-literature context and are not medical advice.