Comparison tool

Melanotan I vs GHK-Cu side-by-side

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Melanotan IGHK-Cu

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Property	Melanotan I	GHK-Cu
Category	Skin & Hair	Skin & Hair
Also known as	Afamelanotide, Scenesse, MT-1, CUV1647, [Nle4, D-Phe7]-alpha-MSH, NDP-MSH	Copper Peptide, Glycyl-L-histidyl-L-lysine copper
FDA approved	Yes	No
Clinical status	FDA Approved (2019) - Erythropoietic Protoporphyria Pre Preclinical I Phase I II Phase II III Phase III IV Phase IV FDA FDA approved	Used in cosmetic products with limited human topical-skincare evidence; the source also notes injectable compounding restrictions and a pending reclassification process. Pre Preclinical I Phase I II Phase II III Phase III IV Phase IV FDA FDA approved
What to expect	Skin tanning, photoprotection, sun sensitivity disorders	Skin rejuvenation, wound healing, hair growth, anti-aging
How it works	Afamelanotide is described as an MC1R agonist acting on melanocytes. Activation of this melanocortin receptor promotes eumelanin production, which the source connects with photoprotection in EPP. The analog differs from native alpha-MSH at positions 4 and 7, changes reported to improve receptor binding and metabolic stability. The source also states that, compared with Melanotan II, Melanotan I is not primarily framed as an appetite or sexual-function peptide because of its relative MC1R selectivity.	GHK-Cu is described as the copper(II) complex of the GHK tripeptide. The source connects its activity to copper binding and possible cellular copper delivery, but also emphasizes effects that go beyond a simple carrier model. Reported laboratory observations include shifts in gene expression, increased fibroblast production of extracellular-matrix components, keratinocyte support, vascular-related activity, and antioxidant or anti-inflammatory signals. The precise mechanism is still not fully defined.
Typical dosing	500-1000 mcg daily (loading), then 500-1000 mcg 1-2x weekly (maintenance) · Daily during loading (1-2 weeks), then 1-2x weekly maintenance · Injected subcutaneously like MT-II	1-2 mg daily injection or 0.05% topical · Once daily · Subcutaneous injection or topical application
Research dosing	16 mg subcutaneous implant · Long-term / as needed before sun season · Subcutaneous implant (not injection)	1-2 mg for injectable protocols · Varies by application · Subcutaneous injection or topical application
Typical duration	Long-term / as needed before sun season	Varies by application
Administration	Subcutaneous implant (not injection)	Subcutaneous injection or topical application
Timing	Evening or before sun exposure With or without food	Evening for skin or recovery contexts With or without food
Evidence level	FDA Approved	Clinical Trials
Possible side effects	Nausea (Reported as common in the source side-effect list.) Skin darkening (Listed as an intended effect.) Headache (Reported side effect; no severity qualifier supplied.) +3 more Fatigue (Reported side effect; no severity qualifier supplied.) Injection site reactions (Reported administration-site effect; source also distinguishes the approved implant from community injection use.) Known safety-profile context in FDA-approved use (The source lists FDA-approved status with known safety profile as safety context rather than a discrete adverse event.)	Generally well tolerated (Reported as a general tolerability statement in the source.) Mild topical irritation, redness, or tingling (Associated with topical use.) Injection-site reactions (Associated with injectable use.) +4 more Possible histamine release (Source advises caution for MCAS or histamine sensitivity.) Copper toxicity risk with excessive use (Risk described for excessive exposure.) Wilson's disease contraindication (Source lists Wilson's disease as contraindicated.) Caution with active cancer (Source flags an angiogenesis-related concern.)
Research summary	The source describes human clinical evidence in erythropoietic protoporphyria, including two multicenter randomized, double-blind, placebo-controlled trials reported in 2015 by Langendonk et al. in the New England Journal of Medicine. Across EU and US sites, 168 people with EPP received either a 16 mg implant or placebo every 60 days. Reported outcomes included longer pain-free sunlight exposure, fewer phototoxic reactions and better disease-specific quality-of-life measures; the US trial example cited median pain-free sunlight time of 69.4 hours versus 40.8 hours. Long-term observational data are described as supporting ongoing benefit with an acceptable safety profile. The source emphasizes that the approval is limited to EPP and that unregulated injectable Melanotan products are not the controlled clinician-administered implant.	The source describes a mixed evidence base. Cell and animal work is reported for wound repair, collagen deposition, fibroblast activity, elastin and growth-factor production, keratinocyte protection, and lung-injury models. Human data are described as small topical cosmetic studies, including facial-cream and eye-cream studies with 71 and 41 participants that reported changes in skin density, thickness, and wrinkle appearance. These data are encouraging for topical skin endpoints but do not establish injected or systemic benefits.
References	New England Journal of Medicine PubMed Central +3 more WikipediaAfamelanotide DermNet NZAfamelanotide PubMed	PubMed PubMed +1 more PubMed
Full profile	View Details	View Details

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Educational use only. This information is aggregated from public research and community reports. It is not medical advice, and dosing details are descriptive, not recommendations. Always consult a qualified healthcare professional.

Property

Melanotan I

GHK-Cu

Category

Skin & Hair

Also known as

Afamelanotide, Scenesse, MT-1, CUV1647, [Nle4, D-Phe7]-alpha-MSH, NDP-MSH

Copper Peptide, Glycyl-L-histidyl-L-lysine copper

FDA approved

Yes

Clinical status

FDA Approved (2019) - Erythropoietic Protoporphyria

Pre
Preclinical
I
Phase I
II
Phase II
III
Phase III
IV
Phase IV
FDA
FDA approved

Used in cosmetic products with limited human topical-skincare evidence; the source also notes injectable compounding restrictions and a pending reclassification process.

Pre
Preclinical
I
Phase I
II
Phase II
III
Phase III
IV
Phase IV
FDA
FDA approved

What to expect

Skin tanning, photoprotection, sun sensitivity disorders

Skin rejuvenation, wound healing, hair growth, anti-aging

How it works

Afamelanotide is described as an MC1R agonist acting on melanocytes. Activation of this melanocortin receptor promotes eumelanin production, which the source connects with photoprotection in EPP. The analog differs from native alpha-MSH at positions 4 and 7, changes reported to improve receptor binding and metabolic stability. The source also states that, compared with Melanotan II, Melanotan I is not primarily framed as an appetite or sexual-function peptide because of its relative MC1R selectivity.

GHK-Cu is described as the copper(II) complex of the GHK tripeptide. The source connects its activity to copper binding and possible cellular copper delivery, but also emphasizes effects that go beyond a simple carrier model. Reported laboratory observations include shifts in gene expression, increased fibroblast production of extracellular-matrix components, keratinocyte support, vascular-related activity, and antioxidant or anti-inflammatory signals. The precise mechanism is still not fully defined.

Typical dosing

500-1000 mcg daily (loading), then 500-1000 mcg 1-2x weekly (maintenance) · Daily during loading (1-2 weeks), then 1-2x weekly maintenance · Injected subcutaneously like MT-II

1-2 mg daily injection or 0.05% topical · Once daily · Subcutaneous injection or topical application

Research dosing

16 mg subcutaneous implant · Long-term / as needed before sun season · Subcutaneous implant (not injection)

1-2 mg for injectable protocols · Varies by application · Subcutaneous injection or topical application

Typical duration

Long-term / as needed before sun season

Varies by application

Administration

Subcutaneous implant (not injection)

Subcutaneous injection or topical application

Timing

Evening or before sun exposure

With or without food

Evening for skin or recovery contexts

With or without food

Evidence level

FDA Approved

Clinical Trials

Possible side effects

Nausea (Reported as common in the source side-effect list.)
Skin darkening (Listed as an intended effect.)
Headache (Reported side effect; no severity qualifier supplied.)

+3 more

Fatigue (Reported side effect; no severity qualifier supplied.)
Injection site reactions (Reported administration-site effect; source also distinguishes the approved implant from community injection use.)
Known safety-profile context in FDA-approved use (The source lists FDA-approved status with known safety profile as safety context rather than a discrete adverse event.)

Generally well tolerated (Reported as a general tolerability statement in the source.)
Mild topical irritation, redness, or tingling (Associated with topical use.)
Injection-site reactions (Associated with injectable use.)

+4 more

Possible histamine release (Source advises caution for MCAS or histamine sensitivity.)
Copper toxicity risk with excessive use (Risk described for excessive exposure.)
Wilson's disease contraindication (Source lists Wilson's disease as contraindicated.)
Caution with active cancer (Source flags an angiogenesis-related concern.)

Research summary

The source describes human clinical evidence in erythropoietic protoporphyria, including two multicenter randomized, double-blind, placebo-controlled trials reported in 2015 by Langendonk et al. in the New England Journal of Medicine. Across EU and US sites, 168 people with EPP received either a 16 mg implant or placebo every 60 days. Reported outcomes included longer pain-free sunlight exposure, fewer phototoxic reactions and better disease-specific quality-of-life measures; the US trial example cited median pain-free sunlight time of 69.4 hours versus 40.8 hours. Long-term observational data are described as supporting ongoing benefit with an acceptable safety profile. The source emphasizes that the approval is limited to EPP and that unregulated injectable Melanotan products are not the controlled clinician-administered implant.

The source describes a mixed evidence base. Cell and animal work is reported for wound repair, collagen deposition, fibroblast activity, elastin and growth-factor production, keratinocyte protection, and lung-injury models. Human data are described as small topical cosmetic studies, including facial-cream and eye-cream studies with 71 and 41 participants that reported changes in skin density, thickness, and wrinkle appearance. These data are encouraging for topical skin endpoints but do not establish injected or systemic benefits.

References

New England Journal of Medicine PubMed Central

+3 more

WikipediaAfamelanotide DermNet NZAfamelanotide PubMed

PubMed PubMed

+1 more

PubMed

Full profile

View Details