GHK-Cu topical vs injected — I've done both, here's the honest comparison

M
Joined 2025
23 posts
mothraMember
3/7/2026 · 2033 views

6 months topical (2% formulation, face, AM/PM), then 8 weeks SC (1mg/day), then back to topical. Same person, same photos, same eye.

Topical: real. Skin texture improves over months. Fine lines soften. Erythema reduces. Tolerable. Slow. Doesn't do anything systemic.

Injected: faster visible skin effect, hair thickening (small but real), vague feeling of improved recovery, bruising at sites, mild discoloration risk. More benefit but more downside.

My take: topical for most people. Injected if you have specific systemic wound healing goals and are ok with the logistics. Don't inject "for skin" — the topical does the skin job at a fraction of the hassle.

Hair people using AHK-Cu for scalp: speak up, is it doing anything you can photograph?

Light
  • GHK-Cu · 2 mg · topical AM · topical

11 Replies

P
Joined 2025
73 posts
3/8/2026

Copper peptide scalp user (AHK-Cu + GHK-Cu topical compounded). 6 months. Photos show modest density increase at the crown. Not minoxidil-level, not finasteride-level, but real. Slow, additive to other interventions.

Healing + skin
  • BPC-157 · 500 mcg · 2x/day · sub-Q
  • GHK-Cu · 2 mg · nightly topical · topical
Q
Joined 2025
31 posts
3/9/2026

Second the "topical for skin, injected for wounds" split. Injected GHK for cosmetic reasons is overkill and you're paying a systemic cost for a surface benefit.

Nightshift
  • DSIP · 100 mcg · pre-bed · sub-Q
  • Epithalon · 10 mg · 10d cycles · sub-Q
H
Joined 2025
212 posts
hexaclinicContributor
3/10/2026

Compounding quality matters enormously with copper peptides. Bad formulation = oxidation = no effect. Most OTC "copper peptide serums" are underdosed or unstable.

Q2 stack
  • CJC-1295 no DAC · 100 mcg · pre-bed · sub-Q
  • Ipamorelin · 200 mcg · pre-bed · sub-Q
  • BPC-157 · 500 mcg · 2x/day · sub-Q
S
Joined 2026
117 posts
3/11/2026

Human data on GHK-Cu topical for skin is actually decent by peptide standards. Small trials, consistent effect sizes. It's one of the few cosmetic peptides I don't dismiss.

D
Joined 2025
122 posts
dr_doubtRegular
3/13/2026

Caution with copper peptides and open wounds/acne — can delay closure in some cases. Also people with Wilson's disease obviously should avoid.

M
Joined 2025
23 posts
mothraMember
3/15/2026

Good point on compounding. Mine was compounded at a legit pharmacy, not drugstore. Difference is probably significant.

Light
  • GHK-Cu · 2 mg · topical AM · topical
P
Joined 2026
36 posts
3/19/2026

Newbie here. Is there a reason to choose GHK over AHK for scalp, or is it a both-together thing?

P
Joined 2025
73 posts
3/19/2026

Most scalp protocols combine. GHK-Cu for general skin/follicle health, AHK-Cu for the specific hair-growth-pathway effect. They're complementary.

Healing + skin
  • BPC-157 · 500 mcg · 2x/day · sub-Q
  • GHK-Cu · 2 mg · nightly topical · topical
M
Joined 2025
23 posts
mothraMember
3/25/2026

One more: don't combine copper peptides and vitamin C serums in the same application. Copper + ascorbic acid = redox mess, both compounds get degraded. Space them hours apart if using both.

Light
  • GHK-Cu · 2 mg · topical AM · topical
L
Joined 2026
14 posts
3/29/2026

Really practical detail — I've been layering C and GHK and wondered why nothing was changing.

F
Joined 2026
20 posts
5/3/2026

Yeah the topical vs injected split makes sense if you're actually measuring this stuff. I ran bloods before and after the SC protocol, collagen markers were up but nothing crazy, and it normalized within a few weeks of stopping. Topical doesn't show systemic changes which honestly makes it safer long term. The hair thing tho, everyone's anecdotal on that. Would be nice if someone actually did scalp microbiopsy or follicle count before/after instead of just "hair feels thicker bro.

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