Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.
| GHK (without copper) | Hexarelin | |
|---|---|---|
| Category | Peptides | Peptides |
| Standard Dose | Research indicates 1-3% concentration in topical formulations. Injectable dosing follows GHK-Cu protocols at 1-2 mg daily. | Research indicates 100-200 mcg administered 1-2 times daily via subcutaneous injection. |
| Timing | Topical application morning and evening. Injectable in evening. | On empty stomach, bedtime preferred. Avoid prolonged continuous use due to rapid desensitization. |
| Cycle Duration | Topical use can be ongoing indefinitely. Injectable cycles 8-12 weeks. | 4-8 week cycles maximum, then 4+ week break. Hexarelin desensitizes faster than other GHRPs. |
| Evidence Level | moderate_human | moderate_human |
GHK (glycyl-L-histidyl-L-lysine) is a naturally occurring tripeptide found in human plasma, saliva, and urine that has an extremely high affinity for copper(II) ions. Even without exogenously complexed copper, GHK rapidly chelates available copper in biological systems, making copper-free GHK functionally similar to GHK-Cu in vivo. The peptide stimulates collagen and glycosaminoglycan synthesis, modulates metalloproteinase activity, resets gene expression patterns toward a healthier state (affecting 31.2% of human genes), and activates wound healing cascades.
Research indicates 1-3% concentration in topical formulations. Injectable dosing follows GHK-Cu protocols at 1-2 mg daily.
Topical application morning and evening. Injectable in evening.
Topical use can be ongoing indefinitely. Injectable cycles 8-12 weeks.
Hexarelin (Examorelin) is a synthetic hexapeptide GHS-R1a agonist and the most potent synthetic GH secretagogue by peak GH release. It stimulates GH release through both pituitary ghrelin receptors and hypothalamic pathways, with mechanisms involving regulation of GHRH and somatostatin. Hexarelin also demonstrates significant cardiac benefits through activation of cardiac GHS-R1a receptors, protecting against ischemia-reperfusion injury and reducing cardiac fibrosis via the CD36 scavenger receptor pathway.
Research indicates 100-200 mcg administered 1-2 times daily via subcutaneous injection.
On empty stomach, bedtime preferred. Avoid prolonged continuous use due to rapid desensitization.
4-8 week cycles maximum, then 4+ week break. Hexarelin desensitizes faster than other GHRPs.
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