Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

What evidence supports cyclical versus continuous GHK-Cu use?

Injectable GHK-Cu follows self-limiting courses of 6–8 weeks, with results assessed at the end of each course before any repeat. Topical GHK-Cu (the alternative route) runs continuously without cycling — it’s a low-dose, locally acting application with no syst

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  • Injectable GHK-Cu follows self-limiting courses of 6–8 weeks, with results assessed at the end of each course before any repeat. Topical GHK-Cu (the alternative route) runs continuously without cycling — it’s a low-dose, locally acting application with no systemic tolerance concerns. There is no evidence that continuous topical use loses effectiveness over time, though some users alternate between GHK-Cu and retinoid-based products to address different repair pathways.