Ipamorelin: Selective growth-hormone secretagogue
A pentapeptide growth-hormone secretagogue notable for releasing GH without the cortisol and prolactin spikes of older GHRPs — not FDA-approved.
What is Ipamorelin?
Ipamorelin is a synthetic pentapeptide growth-hormone secretagogue — it prompts the pituitary to release growth hormone (GH) by acting on the ghrelin receptor (GHS-R1a). Its defining feature is selectivity: in early research it raised GH without meaningfully raising cortisol or prolactin, unlike older growth-hormone-releasing peptides (GHRP-2/6). It is not FDA-approved and is sold as a research compound, frequently paired with CJC-1295.
Published-literature summary: A selective GHRP (growth hormone releasing peptide) that stimulates GH release with high selectivity and minimal impact on cortisol or prolactin — key differentiators from older GHRPs like GHRP-2/6. Research shows improved body composition, bone density, and recovery. Often stacked with CJC-1295 for synergistic GH pulse. (Raun et al. (1998) — Eur J Endocrinol; Svensson et al. (2000) — J Clin Endocrinol Metab)
How Ipamorelin works (mechanism)
Ipamorelin mimics ghrelin at the GHS-R1a receptor, triggering GH release from the pituitary [1]. It was described as the first selective GH secretagogue: in the original characterisation it stimulated GH comparably to GHRH while, unlike GHRP-2 and GHRP-6, not significantly increasing ACTH or cortisol [2]. Growth-hormone secretagogues like ipamorelin are reviewed in the context of body-composition effects [3].
Why it's studied / reported uses
Growth hormone & body composition
Ipamorelin is studied for GH release and downstream effects on body composition, recovery and sleep; the human data are limited and it is used mostly at the research/community level [3].
Other effects
As a ghrelin mimetic it also influences appetite and gut motility, an effect explored in preclinical models [4].
Dosing reported in studies
Route: subcutaneous
A selective GH secretagogue; often stacked with CJC-1295.
Sources: Raun et al. (1998) — Eur J Endocrinol
Selective GHRP with minimal cortisol/prolactin impact in studies. These figures reflect what studies or protocols reported — not a recommendation and not tailored to you.
Calculate a dose in the reconstitution calculator →Common combinations & stacks
Ipamorelin + CJC-1295
The classic GH-peptide pairing combines ipamorelin with CJC-1295 (no DAC): the GHRH analog and the GH secretagogue act on complementary pathways to amplify a GH pulse. This is a community protocol, not an approved or validated regimen.
Safety & side effects
Ipamorelin is not FDA-approved; human safety data are limited and long-term effects are unknown. Reported effects include headache, flushing and injection-site reactions. Growth-hormone secretagogues can affect blood glucose and fluid balance, and are prohibited in competitive sport. Research-chemical sourcing carries purity and dosing-accuracy risks. Consult a licensed physician.
Studies & references
- Do growth-hormone-releasing peptides act as ghrelin secretagogues? — PubMed 11322495
- Ipamorelin, the first selective growth-hormone secretagogue — PubMed 9849822 (Raun et al., Eur J Endocrinol 1998)
- Growth-hormone secretagogues and body composition (review) — NCBI / PMC7108996
- Ipamorelin (ghrelin mimetic) on gastric dysmotility in a rodent model — NCBI / PMC4863553
Frequently asked questions
Is ipamorelin FDA-approved?
No. Ipamorelin is not FDA-approved and is generally sold as a research chemical. It is also prohibited in competitive sport.
What makes ipamorelin different from other GHRPs?
It is selective — in research it raised growth hormone without the cortisol and prolactin increases seen with GHRP-2 and GHRP-6.
How is ipamorelin dosed in studies?
There is no established human therapeutic dose. Commonly reported protocols use roughly 100–300 mcg per dose, one to three times daily (see the dosing section). This is not a recommendation.
Is ipamorelin usually taken with CJC-1295?
In community protocols, yes — the two are frequently combined to amplify a GH pulse. Neither is an approved therapy.
⚠ Research & educational use only. This page is compiled from published research and does not constitute medical advice. Ipamorelin is not FDA-approved and generally sold as a research chemical. Nothing here is a recommendation to use or a prescription. Safe use can only be determined by a licensed physician. Last updated 2026-07-06.