ghk cu day or night GHK-Cu Topical Serum – VEAUTY GHK-Cu Dosage and Protocol: A
Description
Reducing potential skin irritation by controlling the release rate of copper ions

Less common reactions include contact dermatitis (a rash or itching that doesnt resolve), persistent redness, or a localized copper reaction

I do not think anyone can give you really good advice
doi:10.1006/bbrc.1997.8014 Ling C-Q, Li B, Zhang C

In fact, from a holistic perspective, the health of your skin is a reflection of the health of your internal organs (in particular, your digestive system and liver)
