Ipamorelin
Ipamorelin is a selective ghrelin-receptor agonist studied for its ability to stimulate growth hormone release with minimal effect on cortisol or prolactin, making it a common reference compound in GH-axis research.
Part of KYIN Peptides' standard catalogue — see the product page for pricing, or the combined CJC-1295 + Ipamorelin Blend.
What Is Ipamorelin?
Ipamorelin came out of a medicinal-chemistry program at Novo Nordisk in Denmark during the late 1990s, aimed squarely at fixing a known problem with earlier growth-hormone-releasing peptides like GHRP-6 and hexarelin: those compounds reliably stimulated growth hormone release, but they also triggered unwanted spikes in cortisol, ACTH, and prolactin. Novo Nordisk's chemists identified the sequence responsible by systematically stripping down a related peptide series, eventually removing the central Ala-Trp dipeptide found in GHRP-1. The result, first published by Raun and colleagues in a 1998 paper in the European Journal of Endocrinology titled “Ipamorelin, the first selective growth hormone secretagogue,” was a pentapeptide that released growth hormone in research models at a potency comparable to GHRP-6, without the broader hormonal-axis disruption.
Research Focus
Ipamorelin's defining research property — selective ghrelin-receptor activity without broader hormonal-axis disruption — has made it a frequently used reference compound whenever a study needs to isolate growth-hormone-release effects specifically. It sits in KYIN's GHRH & Growth Hormone category alongside Tesamorelin and GHRP-6, and is most often studied paired with a GHRH analog like CJC-1295, as in our CJC-1295 + Ipamorelin Blend. See our GHRH & Growth Hormone research overview, or how it compares to CJC-1295 and Anamorelin as a non-peptide GHRP.
- Growth hormone release research
- Ghrelin receptor selectivity studies
- GH-axis pulsatility research
Clinical & Preclinical Trial Data
The foundational pharmacology paper (Raun et al., European Journal of Endocrinology, 1998) characterized ipamorelin's activity in rat pituitary cells and pigs, not in a human trial — establishing its selectivity (no significant ACTH or cortisol elevation, unlike earlier ghrelin-receptor agonists) but not efficacy or safety in humans for growth-hormone research. A completed human trial does exist, though for a different application entirely: a Phase 2, randomized, double-blind, placebo-controlled trial (Beck et al., International Journal of Colorectal Disease, 2014; 117 adults undergoing bowel resection surgery) tested intravenous ipamorelin for postoperative ileus, drawing on its gastroprokinetic (ghrelin-receptor) activity rather than its growth-hormone effects. Time to first tolerated meal was numerically faster with ipamorelin (25.3 hours versus 32.6 hours for placebo) but did not reach statistical significance (p=.15), and no other efficacy measures differed significantly. No trial has tested ipamorelin for growth-hormone-related or anti-aging research in humans.
Explore the Full Ipamorelin Research Cluster
Every angle of Ipamorelin research in one place:
- Mechanism of Action — selective ghrelin receptor agonism without hormonal-axis disruption
- Discovery & Research History — how Novo Nordisk engineered out GHRP-6's off-target effects
- Ipamorelin vs CJC-1295 — ghrelin receptor vs GHRH receptor mechanisms
- All Four GH-Axis Compounds Compared
- Ipamorelin vs GHRP-6 — the selectivity-engineered successor versus the original secretagogue
- Certificate of Analysis Guide — how to read Ipamorelin's purity testing
- Product & Pricing
Availability
Ipamorelin is part of KYIN Peptides' standard catalogue, sold both individually and combined with CJC-1295 — see the product page or the CJC-1295 + Ipamorelin Blend page for pricing, or contact us to order.
Ipamorelin questions
What is Ipamorelin?
Ipamorelin is a selective ghrelin-receptor agonist developed at Novo Nordisk in the late 1990s, engineered to stimulate growth hormone release with minimal effect on cortisol or prolactin — a selectivity problem earlier GHRP compounds like GHRP-6 did not solve.
Has Ipamorelin been tested in human trials?
Yes, but not for growth-hormone-related research. A Phase 2 trial (Beck et al., International Journal of Colorectal Disease, 2014; 117 patients) tested intravenous ipamorelin for postoperative ileus after bowel surgery, finding a non-statistically-significant improvement in recovery time. No trial has tested ipamorelin for growth-hormone-related or anti-aging research, which is what it's primarily studied for. The foundational pharmacology paper (Raun et al., European Journal of Endocrinology, 1998) characterized its GH-related activity in rats and pigs only.
Does KYIN Peptides sell Ipamorelin?
Yes — Ipamorelin is part of our standard catalogue, both individually and combined with CJC-1295 in our CJC-1295 + Ipamorelin Blend. See the product pages for pricing.
Interested in Ipamorelin?
See pricing and order on the product page, or browse our other GHRH & growth hormone peptides.