Skin & hair
Skin Stack
A carrier peptide plus a signal peptide. GHK-Cu delivers the copper that cross-links collagen into functional fibres; Matrixyl 3000 tells fibroblasts to produce the collagen in the first place.
At a glance
- Sold as
- Separate vials
- The evidence
- Topical GHK-Cu has small human studies over 20+ years, including a 1-month biopsy pilot: 7 of 10 volunteers on a copper-peptide cream made more new collagen, against 5 of 10 on vitamin C and 4 of 10 on tretinoin. Our material names Matrixyl 3000 as the strongest topical signal peptide but cites no study, concentration or protocol for it.Combination-specific research is limited. Treat each compound’s evidence as separate unless a study of the combination itself is named here, and review the complete plan with a qualified clinician.
Running this stack, with the schedule, the vials it takes and a log of what you took, happens in the app: Claritide for iPhone.
Why people explore it
Common reasons for exploring it
- Adults 35+ noticing fine lines, loss of elasticity, dullness or crepey texture
- People who want evidence-based skincare beyond retinoids and vitamin C
- Post-procedure recovery after microneedling, laser or chemical peels
- Anyone who has been spending heavily on serums with weaker evidence
Where clinician input matters
- Anyone with Wilson's disease
- People wanting results in under a month. Collagen synthesis does not move that fast
- Anyone expecting this to address expression lines, which come from muscle movement rather than collagen loss
The science
Read the compound mechanisms
GHK-Cu does two jobs at once: it signals, and it carries copper. As a signal, genomic work using the Broad Institute's Connectivity Map found it modulates expression of over 4,000 human genes, activating repair genes and suppressing genes tied to inflammation and tissue breakdown. That is an epigenetic effect rather than a surface one: it shifts the gene expression profile of aged cells toward patterns seen in younger tissue. As a carrier, it delivers copper to the enzyme lysyl oxidase, which cross-links collagen and elastin fibres into their functional, load-bearing form. Without copper, newly made collagen is structurally weak. It also directly stimulates fibroblasts to produce collagen types I and III, elastin and glycosaminoglycans, and coordinates the breakdown of damaged tissue with the deposition of properly organised replacement tissue rather than scar.
Our material classifies Matrixyl 3000 as a signal peptide: it triggers fibroblasts, the cells in the dermis that manufacture structural protein, to produce collagen. That is a different job from a carrier peptide like GHK-Cu, which delivers the copper that the enzyme lysyl oxidase needs to cross-link collagen into functional fibres. One sends the instruction, the other supplies the material, which is why our sources recommend combining a carrier peptide with a signal peptide rather than choosing between them.
Commonly researched ranges
- GHK-Cu1–2 %
- Matrixyl 3000Per product
| Compound | Amount | Frequency | Timing |
|---|---|---|---|
| GHK-Cu | 1–2 % | Once daily | PM, on clean slightly damp skin, before moisturiser |
| Matrixyl 3000 | Per product | Per product instructions | Same routine |
- GHK-Cu: Do not layer with strong AHAs/BHAs or pure L-ascorbic acid vitamin C. Acidic pH breaks the copper-peptide bond and renders it inert. Alternate AM and PM instead.
- Matrixyl 3000: Our sources publish no concentration or protocol for Matrixyl 3000. Follow the product instructions; we will not invent a figure.
- Duration
- Ongoing daily use. No cycling is needed for topicals. Expect nothing visible for the first four weeks. Clinical trial endpoints land at 8–12 weeks.
Mixing each compound
Not established in available literature. Use the figures printed on your own vial.
Not established in available literature. Use the figures printed on your own vial.
Week by week
GHK-Cu
- Week 1–4 (topical)
Skin texture begins to smooth. Not visible yet: collagen gene activation takes time. Post-procedure healing after microneedling or laser is noticeably faster.
- Week 4–8 (topical)
First visible changes. Skin appears more hydrated and firmer, fine lines begin softening, tone becomes more even.
- Week 8–12 (topical)
Full results as measured in clinical trials: reduced wrinkle depth, increased skin density and thickness, improved elasticity.
- Month 3+ (topical)
Cumulative improvement. The longer it runs, the more collagen accumulates.
- Week 1–2 (injectable)
Wound healing effects appear earliest; reduced inflammation at injury sites.
- Week 4–8 (injectable)
Systemic effects reported: hair growth, joint recovery, skin quality. Note this route has no human trial support.
What it costs
- GHK-Cu: $30–80 per month (1–2% serum, 30 mL)
- Matrixyl 3000: Not established in available literature
The combined figure excludes Matrixyl 3000, for which our sources publish no price.
Cautions
- The regulatory position of topical GHK-Cu got worse in 2026, not better. Non-injectable GHK-Cu was removed from Category 1 on 15 April 2026. It lost enforcement discretion. Injectable GHK-Cu came off Category 2 on the same day because the nominator withdrew, and FDA says it will hold an advisory committee meeting on it before the end of February 2027. Removal from Category 2 is not permission to compound.
- Wilson's disease is a hard contraindication for anything containing copper.
- Never inject a topical skincare-grade GHK-Cu product. Cosmetic formulations are not sterile and are not endotoxin-tested.
- Compatible with retinol, niacinamide, hyaluronic acid and SPF. Incompatible in the same application with strong acids and pure vitamin C.
- GHK-Cu does not cause photosensitivity, unlike retinoids, but wear SPF anyway.
Absence from this list does NOT mean safety. It means lack of research.
Every stack here is free to read, and it stays free. Your own schedule, vials and log live in the app: Claritide for iPhone.