GHK-Cu peptide is most commonly discussed in topical forms, including serums, creams, gels, wound-care preparations, and trial-based topical applications
Injection frequency depends on your individual needs
however, clinical trials in humans are very limited
A recent data science evidence-based approach to determine the top ten ingredients in oral skin supplements (from 71,000 dietary ingredients of which 1781 were found to have at least one skin-related publication assessed in human clinical trials) found that collagen had the most published human skin health-related data, followed by specific antioxidants (especially from natural sources or products) [25]
Skin rejuvenation from within Reveal radiant, youthful skin from the inside out with Klow peptide therapy at Prestige Medical Group
Scientific References Biogerontology (2003) "Epithalon peptide induces telomerase activity and telomere elongation in human somatic cells." (The landmark study on telomeres)