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Catalog/Ipamorelin

Ipamorelin

Selective ghrelin receptor agonist (GHRP) with minimal cortisol / prolactin release.

Overview

Ipamorelin is a pentapeptide GHRP that selectively activates the GHS-R1a (ghrelin) receptor, releasing growth hormone with minimal impact on ACTH, cortisol, or prolactin.

Background

Ipamorelin is a pentapeptide growth-hormone-releasing peptide (GHRP) that selectively activates the ghrelin receptor (GHS-R1a) on pituitary somatotrophs. Its defining feature is selectivity: it releases GH with minimal effect on ACTH, cortisol, or prolactin compared with earlier GHRPs.

Because of that clean profile, it is one of the most studied GHRPs in the research literature and is frequently paired with a GHRH analog such as CJC-1295. It is not FDA-approved.

Mechanism

Selective GHS-R1a agonism.

Key research findings

  • Selective GH release — characterized as the first GHRP to release GH without meaningfully raising ACTH, cortisol, or prolactin (Raun et al., 1998).
  • GHRH synergy — commonly studied alongside GHRH analogs (CJC-1295 / sermorelin) for amplified, pulse-preserving release.
  • Compared to hexarelin — trades raw potency for selectivity: hexarelin releases more GH per dose but recruits cortisol / prolactin and desensitizes the receptor faster.
  • Lower desensitization — its clean receptor profile is studied as more sustainable over repeated exposure.
  • Not FDA-approved — research compound.

How Ipamorelin is made

Behind every vial of Ipamorelin is the same exacting pipeline every research peptide runs — but the chemistry plays out differently for this molecule. Here is how Ipamorelin, specifically, is brought into being.

  1. On paper first

    On paper, Ipamorelin is C38H49N9O5 — about 711.9 daltons of precisely arranged atoms. Before a single bond is made, the target sequence, salt form, and purity threshold are written down as the contract the finished material must meet.

  2. Built residue by residue

    Ipamorelin's chain is short but unusual — it carries D-amino acids and non-natural residues that help it resist enzymatic breakdown, but demand specialized, costlier building blocks and careful coupling on the synthesizer. Its C-terminus is amidated rather than left as a free acid — a defined modification the synthesis has to deliver, not an afterthought.

  3. Purity is won here

    The crude mixture — Ipamorelin plus its deletions and side products — is then separated on preparative HPLC, and where the cut is taken decides the difference between a genuinely pure peptide and a barely-passable one.

  4. Proven, then protected

    A real batch of Ipamorelin proves itself: identity confirmed by mass spectrometry against its ~711.9 Da, purity read directly off an analytical HPLC trace, water and counterion content measured. That batch-specific certificate of analysis is the only honest way to know what is actually in a vial of Ipamorelin — and a short, cold, accountable chain of custody is how that purity survives the trip to your bench.

Walk the full synthesis pipeline

Handling, storage & why purity is hard

Producing Ipamorelin to a genuine purity spec means solid-phase synthesis, preparative HPLC purification, and batch quality control — none of it cheap, and none of it something you can verify by eye.

Don't judge a vial by its cake. A fluffy, good-looking lyophilized powder reflects bulking agents and freeze-drying parameters — not purity. Insist on a batch-specific certificate of analysis.

How peptides are made — the full pipeline

Research areas

  • GH secretion studies
  • Pituitary function

Research-area guides

Latest research

Recent clinical trials and publications mentioning Ipamorelin, pulled automatically from ClinicalTrials.gov and PubMed and refreshed daily. Listings are unfiltered search results, not curated endorsements.

Frequently asked questions

What is ipamorelin?+

Ipamorelin is a selective ghrelin-receptor agonist (a GHRP) studied for growth-hormone release with minimal effect on cortisol or prolactin.

How is it different from other GHRPs?+

Its selectivity — releasing GH without significantly raising ACTH, cortisol, or prolactin — distinguishes it from earlier, less selective GHRPs.

Why is it paired with CJC-1295?+

GHRPs and GHRH analogs act on separate receptors; combining them is studied for synergistic GH release.

Is it approved?+

No — it is a research compound. This page is a research and educational reference.

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Dosing protocols, mechanism, comparisons, and the latest trials — citation-backed answers grounded in PubMed, PubChem, and ClinicalTrials.gov.