Ipamorelin is a selective GH secretagogue (GHRP) that binds to ghrelin receptors (GHS-R) and induces pulsatile endogenous GH secretion, with minimal effect on other hormones. The data show that, unlike GHRP-6/-2, ipamorelin does not significantly increase ACTH/cortisol and does not alter prolactin/gonadotropins — which explains its better tolerability. The article is based on published research and data and on the summary of the Peptology product page.
Summary based on published research and data + product page. Educational content for research use.
- Selective GH secretagogue (GHRP) → pulsatile endogenous GH secretion via GHS-R.
- “Clean” hormonal profile: no notable increase in ACTH/cortisol; no changes in PRL/LH/FSH/TSH.
- Compatible with combination protocols with GHRH analogues (e.g. CJC-1295).
What is Ipamorelin?
A synthetic peptide, a selective GHS-R agonist, designed to activate the GH–IGF-1 axis through physiological pulses of GH rather than through exogenous GH administration. The descriptions highlight the “clean” hormonal profile and good tolerability compared with other GHRPs.
Mechanism of action (GH–IGF-1 axis)
- GHS-R binding (pituitary)
- Pulsatile GH secretion (physiological dynamics)
- Increase in IGF-1 → lipolysis, remodelling, recovery
The selectivity towards GH and the absence of substantial changes in ACTH/cortisol and prolactin are documented in studies, including comparisons with GHRP-6/-2.
What the studies show
- Selectivity for GH – significant GH increase without changes in PRL/LH/FSH/TSH; no increase in ACTH/cortisol, similar to GHRH.
- Efficacy & tolerability – reviews report increases in GH/IGF-1 and rare, usually mild adverse events (AEs), comparable with GHRH analogues.
- Combinations – often examined together with GHRH analogues (e.g. CJC-1295) for synergy (GHRH + GHRP).
- Combinations – often examined together with GHRH analogues (e.g. CJC-1295) for synergy (GHRH + GHRP).
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Note: below we refer to scientific data/summaries. Peptology products are clearly labelled for research use only.
Benefits (research context)
- Natural stimulation of GH with selectivity and a mild hormonal footprint.
- Support for recovery/sleep/regeneration (via GH–IGF-1).
- Metabolic benefit: indirect contribution to lipolysis/body composition (via IGF-1 and GH pulses).
- Combinations: possible synergy with CJC-1295 (without DAC) or other GHRH analogues.
Safety profile
- Most common adverse events (AEs): mild local reactions, transient headache, mild peripheral oedema/discomfort.
- Hormonal “purity”: does not significantly increase ACTH/cortisol and does not alter PRL/LH/FSH/TSH — a key advantage over GHRP-6/-2.
- Anti-doping: GH secretagogues (including ipamorelin) are on the WADA list (prohibited in sport). Always check the current list.
Ipamorelin vs GHRP-6/-2
- Selectivity: Ipamorelin ↑GH without ↑ACTH/cortisol; GHRP-6/-2 can increase cortisol/ACTH.
- Tolerability: milder profile → preferred when selective GH stimulation is sought.
In the Peptology catalogue
The product page includes a mechanism overview, key benefits, FAQ and logistics. From there, navigate to CJC-1295 (without DAC) and Sermorelin for combination models on the GH axis.
Frequently asked questions
Ipamorelin = “injectable GH”?
No. It stimulates endogenous GH via GHS-R; it does not provide exogenous GH.
Does it increase cortisol/prolactin?
No significant increases in ACTH/cortisol; no changes in PRL/LH/FSH/TSH.
Does combining with a GHRH analogue make sense?
Yes, for GHRH+GHRP synergy (e.g. CJC-1295 without DAC).