PEPTIDE
Verified Peptide ReviewLast reviewed: 4 March 2026

Compound Profile · Skin

GHK-Cu

GHK-Cu is a naturally occurring copper-binding tripeptide that has been studied extensively in skin biology and wound healing literature.

LegalResearch onlyEvidenceModerateHuman useRestricted
7.2/ 10

Peptide Score

Evidence

7.6

Safety

8.8

Regulatory

8.0

Transparency

8.2

Quick verdict

Most-studied cosmetic peptide for skin biology — topical formulations widely used. Injectable use remains research-only; not approved.

Reality check

What this isn't

  • Cosmetic vs. injectable distinction critical — topical widely approved, injectable is not
  • Injectable form not approved for human use by TGA or other agencies
  • Copper content requires monitoring in injectable forms
  • Allergic reactions possible, especially in sensitive individuals
  • Topical efficacy superior to injectable in published cosmetic trials
  • Long-term systemic effects (injectable) unknown
  • Educational research review only — not medical advice

Results snapshot

Collagen synthesis stimulation

Gene expression and collagen production (in-vitro)

12

Weeks

Approved

Trial phase

What this means: Extensively documented effects on collagen, elastin and fibroblast activity in cell and tissue models. Multiple topical clinical trials in humans (cosmetic pathway). Injectable form never advanced to clinical approval; long-term human safety uncharacterized.

Reported timeline

What participants experienced

  1. 1

    In-vitro studies

    Fibroblast collagen synthesis demonstrated

  2. 2

    Topical clinical trials

    Cosmetic efficacy and safety documented; regulatory approval for cosmetic use in multiple markets

  3. 3

    Injectable research

    Limited human data; systemic effects not established

  4. 4

    Current status

    Topical formulations widely available; injectable remains research-only

Deep dive

Full GHK-Cu review

A naturally occurring tripeptide that binds copper(II).

Studied for collagen, elastin and wound healing pathways.

CompareResearch-gradeSafety