Skin & Cosmetic
GHK-Cu
Copper Tripeptide-1
This one's different from most of the list: it's a copper-based skincare ingredient, not something you'd inject. It prompts skin cells to make more collagen, which is why it turns up in anti-ageing creams and hair products. Properly trial-tested, and no prescription needed.
Copper-binding used in cosmetics. Evidence is route- and formulation-specific; topical clinical evidence is limited and injectable/systemic claims are not established.
How well studied
Tier Guide: A = Well studied, B = Some good studies, C = Early evidence & D = Barely studied
Mostly animal studies or very small early trials in humans. We don't really know yet how it behaves in people.
UK status
How you could legitimately come across it here, if at all
This is sold in skincare as a cosmetic ingredient rather than as a medicine. Cosmetics are regulated for safety, but they are not tested and authorised the way medicines are.
Evidence strength and UK regulatory status answer different questions.
Overview
How it works
Copper gets carried straight to skin cells, which respond by producing more collagen, the protein that keeps skin firm and speeds up healing.
Delivers copper directly to skin cells, signalling them to produce more collagen and support tissue repair.
Reported benefits
- Mechanistic and preclinical studies support roles in extracellular-matrix remodelling and tissue repair
- Small human topical studies exist, but objective anti-ageing benefit has not been robustly established
- Hair evidence often involves combination formulations or related copper peptides rather than GHK-Cu alone
Who it's typically used for
Timeline to results
Safety & UK access
Dosage
No established human dose. Cosmetic topical products carry formulation-specific concentrations set by the manufacturer, and injected or systemic GHK-Cu has no established human treatment regimen at all.
Side effects
- Mild redness at the application site (topical cosmetic use)reported
- Itching or contact irritation (topical cosmetic use)reported; patch testing advised
- Injected or systemic useinsufficient human data
Getting it in the UK
This is sold in skincare as a cosmetic ingredient rather than as a medicine. Cosmetics are regulated for safety, but they are not tested and authorised the way medicines are.
Where it turns up
- Over the counter as a cosmetic
Sold openly in skincare as a cosmetic ingredient, not as a medicine. Cosmetics are regulated for safety, not tested and authorised the way medicines are.
Sold as a standard cosmetic ingredient; no prescription or clinic required for the topical route
MHRA: the UK regulator that assesses whether a medicine is safe and works before it can be authorised for use here. Something not being MHRA-licensed does not automatically mean it is illegal, and it does not mean it is safe.
This is background information about UK regulation, not advice about what you can or should obtain.
Evidence & sources
Why this rating?
The A to D rating shown above comes from our earlier editorial review and is still waiting to be migrated into the structured review record below. That is a gap in our record-keeping, not a sign the rating is wrong.
Evidence fingerprint
No route and indication scope has been published for this profile yet, so no fingerprint is shown.
Sources
Structured source audit not yet published for this profile. The references behind this page are being catalogued one compound at a time, and this one has not been through that process yet.
Content freshness
- Last reviewed
- 24 Sept 2026
- Regulatory status last checked
- 21 Aug 2026