Review Article
GHK-Cu may prevent oxidative stress in skin by regulating copper and modifying expression of numerous antioxidant genes
Pickart L, Margolina A. Cosmetics. 2018
Compare
Side-by-side observational reports from PeptIQ users. This compares self-reported patterns — not clinical head-to-head trials.
Last reviewed . By the PeptIQ team.
From check-in ratings — separate from side effects logged below. Side effects are logged separately from overall experience. A favorable check-in can still include nausea, fatigue, or injection-site reactions.
Favorable 3% · Mixed 97% · Unfavorable overall 0%
Benefits users selected when logging a favorable or mixed check-in.
Side effects are logged separately from overall experience. A favorable check-in can still include nausea, fatigue, or injection-site reactions.
Median bucket: 2–3 mg · Most common: 2–3 mg
Reports span 0 to ≥ 5 mg (open-ended top bucket)
Anonymized self-reports from PeptIQ users — not prescribing guidance. Buckets group similar logged amounts; open-ended top buckets mean “at least” that dose.
Among repeat reporters, 89% said they felt similar to their last entry, 11% more positive, and 0% more negative.
Overall, repeat reporters leaned more positive than their previous entry.
Median gap between entries: 46 days · Based on 45 repeat reporters
From check-in ratings — separate from side effects logged below. Side effects are logged separately from overall experience. A favorable check-in can still include nausea, fatigue, or injection-site reactions.
Favorable 98% · Mixed 2% · Unfavorable overall 0%
Benefits users selected when logging a favorable or mixed check-in.
Side effects are logged separately from overall experience. A favorable check-in can still include nausea, fatigue, or injection-site reactions.
Median bucket: 2+ mg · Most common: 2+ mg
Reports span 0.2 to ≥ 2 mg (open-ended top bucket)
Anonymized self-reports from PeptIQ users — not prescribing guidance. Buckets group similar logged amounts; open-ended top buckets mean “at least” that dose.
Among repeat reporters, 92% said they felt similar to their last entry, 8% more positive, and 0% more negative.
Overall, repeat reporters leaned more positive than their previous entry.
Median gap between entries: 127 days · Based on 25 repeat reporters
Published sources linked on the GHK-Cu and Melanotan I wiki pages.
Review Article
Pickart L, Margolina A. Cosmetics. 2018
PubMed
Pickart L. J Biomater Sci Polym Ed. 2008
PubMed
Pickart L, Margolina A. Biomed Res Int. 2014
ClinicalTrials.gov
ClinicalTrials.gov. Clinical trial registry. 2024
PubMed
Pickart L, Vasquez-Soltero JM, Margolina A. BioMed research international. 2015
PubMed
Yang X, Zhang Y, Huang C, et al. Macromolecular bioscience. 2022
PubMed
Langendonk JG, Balwani M, Anderson KE, et al. N Engl J Med. 2015
PubMed
2024
PubMed
Sweeney P, Gimenez LE, Hernandez CC, et al. Nature reviews. Endocrinology. 2023