Head-to-head
Ipamorelin vs GHK-Cu
A field-by-field comparison of Ipamorelin and GHK-Cu drawn from the PeptideIndex database: mechanism, evidence grade, half-life, administration route, reported dosing, side effects, storage and legal status. They belong to different categories — growth hormone and skin & hair — so this page focuses on what each one actually does rather than which is "better".
Ipamorelin vs GHK-Cu at a glance
| Attribute | Ipamorelin | GHK-Cu |
|---|---|---|
| Category | Growth hormone | Skin & hair |
| Evidence grade | Moderate | Moderate |
| Also known as | NNC 26-0161 | Copper peptide, Glycyl-L-histidyl-L-lysine copper |
| Chain | Pentapeptide (Aib-His-D-2-Nal-D-Phe-Lys-NH2) | Tripeptide (Gly-His-Lys) with copper(II) |
| Mechanism | Acts as a ghrelin receptor (GHS-R1a) agonist on the pituitary, triggering a clean GH pulse. Its selectivity avoids the appetite and cortisol effects seen with older secretagogues like GHRP-6. | Delivers copper into cells and resets gene expression toward a younger profile, upregulating collagen, elastin and glycosaminoglycan synthesis while activating antioxidant defences and hair-follicle enlargement. |
| Reported benefits | Clean GH pulse without hunger spikes · Better sleep quality and recovery · Mild fat-loss and body-composition support | Increased collagen and elastin production · Improved skin firmness and reduced fine lines · Hair-follicle stimulation · Accelerated wound healing |
| Reported side effects | Mild headache · Injection-site redness · Light-headedness shortly after dosing | Skin irritation or redness · Copper accumulation with excessive systemic use · Injection-site swelling |
| Half-life | About 2 hours | Not applicable topically; short systemically |
| Administration | Subcutaneous injection, 1–3 times daily | Topical serum, microneedling adjunct or subcutaneous injection |
| Dosing overview | 200–300 mcg per dose, often 100–300 mcg before bed | Topical 1–3% serum daily; injectable protocols vary widely |
| Storage | Reconstituted vials refrigerated 2–8 °C, stable ~4 weeks | Cool, dark place; the solution is characteristically deep blue |
| Legal status | Not FDA-approved; compounding restrictions apply in the US. Banned in sport. | Widely available as a cosmetic ingredient; injectable use is unapproved. |
Key differences between Ipamorelin and GHK-Cu
Different categories, different goals
Ipamorelin is indexed under growth hormone, while GHK-Cu sits under skin & hair. They are not substitutes for one another: Ipamorelin is described as "The most selective of the growth-hormone secretagogues, valued because it lifts GH without meaningfully raising cortisol or prolactin." and GHK-Cu as "A naturally occurring copper-binding tripeptide with the best-supported cosmetic profile of any peptide, plus hair and wound-healing uses."
Mechanism of action
Ipamorelin: Acts as a ghrelin receptor (GHS-R1a) agonist on the pituitary, triggering a clean GH pulse. Its selectivity avoids the appetite and cortisol effects seen with older secretagogues like GHRP-6. GHK-Cu: Delivers copper into cells and resets gene expression toward a younger profile, upregulating collagen, elastin and glycosaminoglycan synthesis while activating antioxidant defences and hair-follicle enlargement.
Half-life and dosing frequency
Ipamorelin is listed at about 2 hours; GHK-Cu at not applicable topically; short systemically. That difference is what drives the reported schedules: 200–300 mcg per dose, often 100–300 mcg before bed versus Topical 1–3% serum daily; injectable protocols vary widely
Route of administration
Ipamorelin is administered by subcutaneous injection, 1–3 times daily. GHK-Cu is administered by topical serum, microneedling adjunct or subcutaneous injection.
Legal and regulatory status differs
Ipamorelin: Not FDA-approved; compounding restrictions apply in the US. Banned in sport. GHK-Cu: Widely available as a cosmetic ingredient; injectable use is unapproved. This is usually the most practical difference between two compounds, because it determines whether a supply chain is labelled and regulated at all.
Handling and storage
Ipamorelin is stored reconstituted vials refrigerated 2–8 °c, stable ~4 weeks. GHK-Cu is stored cool, dark place; the solution is characteristically deep blue.
What Ipamorelin and GHK-Cu have in common
- Evidence grade: both listed as Moderate
Each compound in brief
Ipamorelin
Growth hormone · Moderate evidence
The most selective of the growth-hormone secretagogues, valued because it lifts GH without meaningfully raising cortisol or prolactin.
Considerations: Weakest GH release of the GHRPs — usually stacked with CJC-1295 · Effects build over weeks, not days · Dose ceiling: more than ~300 mcg per pulse gives diminishing returns
GHK-Cu
Skin & hair · Moderate evidence
A naturally occurring copper-binding tripeptide with the best-supported cosmetic profile of any peptide, plus hair and wound-healing uses.
Considerations: Topical formulations are the safest starting point · Do not combine directly with vitamin C or strong acids in the same layer · Injectable use can cause significant flushing and irritation
Related comparisons and reading
Every figure on this page is reproduced from the compound profiles in this database and reflects published literature and commonly reported protocols. It is educational information, not medical advice, and not a recommendation to use either compound. See the medical disclaimer.