Growth & GH-Axis

Hexarelin

Growth-hormone secretagogue (GHRP) / ghrelin receptor agonist

A synthetic hexapeptide studied in growth-hormone secretagogue research.

Also referenced as: Examorelin

6 aat½ Short, on the order of tens of minutes (reported approximately 55 minutes)

Overview

Hexarelin (Examorelin) is a synthetic hexapeptide growth-hormone secretagogue, a structural analog of GHRP-6. It was developed as a potent GH-releasing peptide.

At a glance

ClassGrowth-hormone secretagogue (GHRP) / ghrelin receptor agonist

CategoryGrowth & GH-Axis

SequenceHis-D-2-methyl-Trp-Ala-Trp-D-Phe-Lys-NH2

Chain length6 amino acids

Molecular weight887.0 g/mol

Half-lifeShort, on the order of tens of minutes (reported approximately 55 minutes)

Typical formLyophilized powder

AliasesExamorelin

Use designationResearch / in-vitro only

Regulatory statusHexarelin is not approved by the FDA or EMA for any indication; it is used in research contexts only and is not an approved medicine.

What Hexarelin does

Hexarelin is a synthetic hexapeptide growth hormone-releasing peptide (GHRP) that acts as a potent agonist of the ghrelin receptor (GHS-R1a), stimulating a strong GH pulse from the pituitary. Among the GHRPs it is one of the most powerful GH releasers, but its distinguishing research feature lies elsewhere: hexarelin also binds the CD36 scavenger receptor, which is expressed in cardiac and vascular tissue. Through this GH-independent CD36 pathway it has shown direct cardiovascular actions in animal models — cardioprotective and anti-fibrotic effects on the heart that do not depend on growth hormone at all. This dual receptor activity makes hexarelin a distinct research subject compared with the more GH-focused GHRPs.

As a ghrelin mimetic it works like the other GHRPs — amplifying GH pulse amplitude, suppressing somatostatin, and raising downstream IGF-1 — but it is less selective than ipamorelin, and can raise cortisol and prolactin at higher exposures. A well-documented limitation in human pharmacology is desensitization: with continued administration the GH response to hexarelin attenuates over time as the receptor down-regulates, which has complicated its development as a GH therapy.

Evidence spans early human GH-secretion pharmacology and a substantial body of preclinical cardiac work; hexarelin is not an approved drug, and its cardiac findings in particular remain animal/experimental.

Effects reported in research

Stimulated a potent GH pulse via GHS-R1a agonism — among the strongest of the GHRPs (human pharmacology).
Bound the CD36 scavenger receptor in cardiac/vascular tissue, producing GH-independent cardioprotective effects (animal models).
Reduced cardiac fibrosis and improved cardiac function/recovery after ischemic injury in animal studies.
Raised downstream IGF-1 following GH release.
Showed GH-response desensitization / tachyphylaxis with continued dosing in humans — a notable limitation.
Elevated cortisol and prolactin at higher exposures (less selective than ipamorelin).
Suppressed somatostatin tone as part of its secretagogue action.
Cardiovascular findings remain preclinical; not an approved therapeutic.

Effects listed reflect findings reported in the research literature — many in animal or in-vitro models. Listing an effect is not a claim of efficacy or a therapeutic indication in humans.

Mechanism of action

Hexarelin is an agonist of the growth-hormone secretagogue receptor (GHS-R1a, ghrelin receptor), stimulating GH release from the pituitary. It is a potent GH secretagogue and also binds the CD36 scavenger receptor, which underlies research interest in cardiovascular effects. It can stimulate ACTH, cortisol, and prolactin release, and its GH response is known to attenuate (desensitize) with repeated exposure.

Mechanistic description reflects published research-literature understanding. Much peptide research is preclinical (in-vitro or animal-model); mechanism in humans may differ and is not established for many compounds.

What it's studied for

Research contexts in which Hexarelin appears in the literature. Listing a research area is not a claim of efficacy or a therapeutic indication.

Key characteristics

One of the more potent GHRPs for GH release
Also binds CD36, giving it GH-independent cardiovascular research interest
Can raise cortisol, ACTH, and prolactin, unlike the more selective ipamorelin
Prone to tachyphylaxis (attenuated GH response) with repeated administration
Hexapeptide structurally related to GHRP-6

Reported research dosing reference only

Educational reference, not dosing guidance. The figures below summarize amounts reported in published research and research-community protocols, provided for educational and research context only. They are not medical advice, not a recommendation, and not instructions for human use. Hexarelin is a research compound.

Hexarelin is referenced at low microgram-per-kg doses in the research literature, reflecting its high potency. These are reference figures for research context only, not dosing guidance for humans.

Body-weight-scaled reference: ~1-2 mcg/kg per dose in animal models; ~2 mcg/kg referenced in human studies
Common research-protocol reference: ~100 mcg per administration

Reported frequencyReported 1-3 times daily in research protocols; intermittent dosing is noted to limit receptor desensitization

ReconstitutionLyophilized; typically reconstituted with bacteriostatic water for research use

Most potent GHRP (roughly 10x GHRP-6); desensitization is a documented consideration. Reference figures only, not human dosing guidance.

How it compares

Hexarelin is among the most potent GHRPs and uniquely binds CD36 (of cardiovascular interest), but it is less selective than ipamorelin and shows notable receptor desensitization.

Commonly studied alongside

Compounds frequently researched together with Hexarelin in the literature. Cross-referenced for research context — not a usage or combination recommendation.

CJC-1295 (with DAC)GHRP + GHRH analog combination is studied for synergistic GH-pulse amplification.SermorelinGhrelin-receptor agonist co-studied with a GHRH analog to engage both GH-release pathways.

Compare and calculate

Side-by-side pages for the pairings the literature already documents for Hexarelin, plus the unit-conversion reference for a reconstituted vial. Factual comparisons of documented characteristics — not a recommendation to combine or use any compound.

Handling & Stability

Lyophilized peptides are stored cold, protected from light, and reconstituted only at the time of intended in-vitro work.

Avoid repeated freeze-thaw cycles
Verify supplier lot and Certificate of Analysis
Follow institutional lab-safety protocols

Analytical & COA Concepts

Reputable research suppliers publish a third-party Certificate of Analysis per batch. Key analytical concepts referenced in COAs include:

Category Context

Hexarelin sits in the Growth & GH-Axis area of the PeptiDex library.

Research Supplier Listing

Where researchers source Hexarelin

For researchers studying Hexarelin, third-party suppliers such as Practically Natty Peptides offer research-grade material, third-party tests every batch and provides Certificates of Analysis on request, and ship from the US.

Explore Research Suppliers →

PeptiDex does not maintain a direct supplier listing for this compound. The link above goes to a third-party research-supplier directory.

Frequently asked questions

What is hexarelin?

Hexarelin is a synthetic hexapeptide growth hormone-releasing peptide (GHRP) and ghrelin-receptor (GHS-R1a) agonist. It is noted in the research literature as one of the most potent GHRPs, driving GH release at lower doses than GHRP-6.

How does hexarelin differ from GHRP-6?

Hexarelin's sequence is nearly identical to GHRP-6 but carries a 2-methyl modification on the D-tryptophan residue. This substitution increases proteolytic resistance and potency, so hexarelin achieves comparable GH release at roughly 10-fold lower doses than GHRP-6 in research models.

Is hexarelin known for receptor desensitization?

Yes. The research literature notes that hexarelin, as a very potent GHS-R agonist, can lead to receptor desensitization with continuous high-dose exposure, which is a consideration in study design examining sustained versus intermittent stimulation.

Does hexarelin have cardiac-related research interest?

Beyond GH release, hexarelin has been studied for binding to CD36 and effects in cardiac tissue models, making it of interest in cardiovascular research distinct from its pituitary GH-secretagogue activity.

Is hexarelin an approved drug?

No. Hexarelin is not an approved medication; it has been used in research settings and is available only as a research chemical.

Answers are educational summaries of research-literature context and do not constitute medical advice. See the Research Library, COA guide, and Storage & Handling guide for more.

References

Primary literature indexed in PubMed for Hexarelin. Listing a study records that it exists and is indexed — it is not a claim of efficacy, a therapeutic indication, or an endorsement of its conclusions. Much of this literature is preclinical (in-vitro or animal-model).

The growth hormone secretagogue hexarelin improves cardiac function in rats after experimental myocardial infarction Endocrinology, 2000. PubMed 10614623
The cardiovascular action of hexarelin J Geriatr Cardiol, 2014. PubMed 25278975

Each reference was checked against its PubMed record on 2026-07-28: the PMID resolves and the title, journal and year match. Where no indexed literature exists for a compound, PeptiDex says so rather than substituting a citation about a different molecule. See the editorial policy.