Can you use Copper peptides (GHK-Cu) with Vitamin C (L-ascorbic acid)?

Q: Can you use Copper peptides (GHK-Cu) with Vitamin C (L-ascorbic acid)?

Separate — AM / PM. A commonly-advised split: many formulators keep copper peptides and L-ascorbic acid in separate routines (one AM, one PM), on the theory that a low-pH vitamin C and the copper complex don't sit well together. Direct cosmetic evidence is limited, but the split is easy to follow.

Separate — AM / PMEvidence · Commonly advised

A commonly-advised split: many formulators keep copper peptides and L-ascorbic acid in separate routines (one AM, one PM), on the theory that a low-pH vitamin C and the copper complex don't sit well together. Direct cosmetic evidence is limited, but the split is easy to follow.

Commonly advised: Frequently recommended by formulators; direct evidence can be limited.

In practice: use one in the morning and the other in the evening.

Copper peptides (GHK-Cu)

INCI · Copper Tripeptide-1

A copper-bound tripeptide used in serums for the look of firmness and a more even tone.

Read the reference →

Vitamin C (L-ascorbic acid)

INCI · Ascorbic Acid

An antioxidant active, typically used in the morning for a brighter-looking, more even complexion.

All pairings →

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Cosmetic layering guidance for the look and feel of your routine — not medical advice. Patch-test new combinations.

This site provides neutral scientific reference and sells only products lawful in your region. Nothing here is medical advice, a recommendation, or an offer to supply unapproved medicines. No dosing or administration is published for research compounds. Cosmetic peptides per Regulation (EC) 1223/2009. Unapproved injectable peptides are neither sold nor advertised in the EU (Directive 2001/83/EC, Title VIII). © 2026 Vallydia SL — Registered in Spain.