GHK-Cu

most data

Also seen as: copper peptide, GHK copper

The Dose Guy’s verdict

Sep 1, 2026
3 sources

Two different compounds wearing the same name, depending on how you use it. Topical GHK-Cu for skin and hair has decades in cosmetic formulations and strong cell work, though the one small human trial mostly missed on its endpoints. Injectable GHK-Cu for systemic healing has no human data behind it at all. If you are here for skin, the case is cell data plus a long cosmetic track record, honest but real. If you are here for tendon or joint repair via injection, BPC-157 and TB-500 have more community track record for structural healing.

Would I take it?Topically, yes. Injected, you're guessing.

What it is

A naturally occurring tripeptide bound to a copper ion. Your body makes it: GHK-Cu circulates in plasma, declines with age, and plays a role in wound repair, collagen remodeling, and anti-inflammatory signaling. The mechanism is broad. It stimulates collagen and glycosaminoglycan synthesis, upregulates growth factors in damaged tissue, and modulates matrix metalloproteinases that remodel scar tissue and extracellular matrix.

In the healing column it sits in an odd position. The published cell and tissue work is deep, dose-dependent collagen stimulation in fibroblasts, growth factor production, matrix remodeling, but almost all of it is about skin and topical delivery. The injectable systemic use that the community runs for joint and tissue repair is a different bet, one that borrows the topical mechanism without its own evidence. GHK-Cu’s strength is skin and hair, not structural healing.

What the research shows

Strong cell and tissue work, mostly about skin. One small human trial. No injectable human data:

In thirteen patients after laser resurfacing, topical GHK-Cu did not significantly improve erythema, wrinkles, or objective skin quality versus the control regimen. Patient-rated overall skin quality favored GHK-Cu at 12 weeks, p=0.04.Arch Facial Plast Surg 2006 · RCT · n=13

GHK-Cu stimulated collagen synthesis in human fibroblasts starting at picomolar concentrations, with peak stimulation at nanomolar levels and no change in cell number.J Pept Res 1988 · fibroblast study

In rats after ACL reconstruction, intra-articular GHK-Cu reduced knee laxity at 6 weeks with p=0.009, but the difference was gone by 12 weeks. The 0.3 mg/mL group had higher graft stiffness than saline at 6 weeks with p=0.026, while ultimate load, gait, and histology did not differ among groups.Wound Repair Regen 2015 · rat ACL · n=72

No human injectable efficacy or safety study exists. The topical-to-injectable leap is assumption, not evidence.as of Aug 2026

Realistic protocols

For skin, the evidence supports topical use: creams and serums at concentrations in the parts-per-million range, applied to the face or target area once or twice daily. That is the studied route and the one with a track record. Microneedle delivery pushes more through the skin barrier if you want deeper penetration.

For injectable use, the community runs 1 to 2 mg subcutaneously once daily, sometimes near an injury site, sometimes systemically. This protocol is extrapolated from the topical mechanism and community experience, not from any human dosing study. If you are running it injected, treat it as experimental: start low, run short cycles of four to six weeks, and do not expect the topical evidence to guarantee results through a different route. Reconstitute with bacteriostatic water and refrigerate. The copper complex gives the solution a faint blue tint, that is normal.

For topical use, avoid layering GHK-Cu with strong acids or retinoids in the same application. Copper peptides and low-pH actives do not play well together, and the copper can oxidize in combination. Apply them at different times of day. The blue-green tint can stain light fabrics, so let it absorb before dressing.

TopicalCream/serum, 1–2x dailyThe studied route. Parts-per-million concentrations in cosmetic formulations.

Injectable1–2 mg/day sub-qCommunity protocol, no human dosing data behind it. Start at the low end.

Duration4–6 weeks injectableFor injectable cycles. Topical can run continuously.