# GHK-Cu (injectable)

Hugely popular for skin tightening and hair; supraphysiologic systemic dosing with no human data.

- Page: https://peprank.xyz/peptides/ghk-cu-injectable
- Category: Skin & hair (Research peptide)
- Also known as: copper peptide; glycyl-L-histidyl-L-lysine copper; main component of 'GLOW'/'KLOW'
- Routes: Injection
- Sequence: GHK (Cu(II) complex)
- Safety tier: Strict: Avoid · Balanced: Avoid · Evidence only: Caution
- Risk axes (0 none to 3 severe): Seen harm 1, Mechanism 2, Data gap 3, Silent harm 3, Product 3
- Positive: 47% of 32 graded reports glowing or positive, shrunk toward the 49% all-report average by 8 reports' weight
- Rank: #40 of 61 research peptides
- Graded reports: 32 (Glowing 8, Positive 7, Mixed 3, Nothing 4, Negative 4, Bad reaction 6)
- Evidence: Small human studies — Topical only; no human trials of injection
- Access: Grey market
- Onset: Users describe a 'copper ugly' phase of breakouts or dull skin in weeks 1-6 for some; visible skin and hair changes are usually reported from weeks 4-12, sometimes not until month 3.
- Lasts: Short half-life (users cite about 2 hours subq), so it is pinned daily; gains are said to hold for weeks after a cycle ends but fade without maintenance.
- Cost per month: ≈ €20–40 (at 1–2 mg/day, Semax Polska at €0.66/mg)
- Dose users report: 1.5–3.2 mg/day (median 2 mg, n=11)
- Updated: 2026-10-30

**Why Avoid under the strict bar:** Borderline: theoretical growth-factor/angiogenic signalling at supraphysiological systemic doses with no human injectable safety data. Topical GHK-Cu gives much of the skin benefit without this.

## What users report

Many glowing before/after posts: firmer skin, fewer spots, brighter under-eyes, faster hair and nail growth, milia clearing. Results build over 6-20 weeks, often after a temporary 'copper ugly' phase. Roughly 25% see nothing, especially under 35. Injections sting and leave welts unless diluted, and some get hard lumps or lasting marks. A minority say their skin got duller, saggier or broke out for good rather than passing through the 'uglies', and a recurring cluster report systemic reactions in the first days or weeks: flu-like aches, lightheadedness, vomiting, or itchy marks all over the body. Serum copper usually stays normal.

**Effects:** skin firmness and tone; less under-eye hollowness/darkness; faster hair and nail growth; improved wound/scar healing

**Downsides:** painful, itchy injection welts if concentrated; temporary 'copper ugly' phase; cost

**Risks:** Borderline/theoretical: stimulates growth factors (VEGF, bFGF) and angiogenesis in wound models, at systemic levels far above physiological; FDA flagged immunogenicity/aggregation for injectable GHK-Cu; limited human injectable data; Chronic copper load (small; serum copper usually normal)

**Typical use:** 1-2 mg/day subQ (some up to 4 mg), diluted with extra bacteriostatic water, often 5 days on / 2 off for 12 weeks.

**Getting it:** Research-peptide vendors (50-100 mg vials, alone or in GLOW/KLOW blends); some US med-spas and telehealth clinics prescribe compounded vials. FDA lists injectable GHK-Cu among substances with safety concerns.

**Stacked with:** BPC-157 and TB-500 (GLOW) or plus KPV (KLOW) (The usual way it is sold and pinned; users say BPC-157 or KPV in the same syringe reduces the sting and welts.); Topical GHK-Cu or AHK-Cu serum (Many pin and apply topically at once, or switch to topical between injectable cycles.); Tretinoin and red light (Common skin-care pairing in r/30PlusSkinCare; makes it hard to tell which did what.); Zinc (Taken to balance the extra copper and, some claim, to reduce injection-site reactions.)

## Risk profile

- **Seen harm 1/3:** No published case reports, but clinicians describe raised copper and liver enzymes in self-injectors, and first-hand reports include an ER visit (confounded by tirzepatide), near-fainting on isotretinoin and weeks of vomiting after a dosing error. Isolated and confounded.
- **Mechanism 2/3:** Stimulates VEGF, bFGF and angiogenesis in animal wound models, and injected doses reach systemic levels far above the body's own; copper accumulation adds a second, slower path.
- **Data gap 3/3:** No human study has ever injected GHK-Cu; all human data are topical. FDA flagged immunogenicity for injectable forms.
- **Silent harm 3/3:** Angiogenic tumour promotion and slow copper overload of the liver would both be silent; liver enzymes and copper show only on blood tests.
- **Product 3/3:** Grey-market 50-100 mg vials, alone or in GLOW/KLOW blends, plus some med-spa compounded vials.
- **Never if:** Active cancer or a history of cancer; Wilson disease or other copper-handling disorders; Liver disease; Pregnancy or breastfeeding (no human reproductive data)

## Top reports

- Glowing, skin-hair, 1 mg nightly: “I noticed that hair wasn't falling out when I was showering. ... I used to have chicken skin on my tricep area up to my shoulder and now that is gone.” — [r/Biohackers](https://www.reddit.com/r/Biohackers/comments/1sphw3t/ghkcu_before_and_after/)
- Glowing, skin-hair, 5 mg 4x/week: “Struggled with adult acne the last 5 years and tried everything, started GHK-Cu in March this year and am blown away by the results.” — [r/BodyHackGuide](https://www.reddit.com/r/BodyHackGuide/comments/1w9nj9n/5_month_ghkcu_update/)
- Glowing, skin-hair: “initially had the copper ugliest for maybe 2 weeks then it went away. My skin has now gotten so much better it’s actually insane.” — [r/Biohacking](https://www.reddit.com/r/Biohacking/comments/1w8bg1x/ghkcu_is_the_goat_peptide/)
- Glowing, skin-hair, 2 mg/day rising to 4 mg/day: “I’ve (60F) been on GHK-Cu daily since January. Started at 2mg/day, now at 4mg/day. The stuff is amazing. I haven’t had my hair stop going gray, but it does grow faster, same with my nails.” — [r/Biohacking](https://www.reddit.com/r/Biohacking/comments/1xg530o/ghkcu_20_week_update_read_the_full_post/19rp120so1539/)
- Glowing, skin-hair: “I've done one month of injectable copper and I am GLOWING. Also my hands look younger. I'm 43 and spend a fortune on my skin but this took it to another level.” — [r/SkincareAddiction](https://www.reddit.com/r/SkincareAddiction/comments/1cqui3m/product_question_has_anyone_tried_ghkcu/nhzmk0e/)

## Cheapest in Europe

- [Europa-Peptide](https://europa-peptide.de/en/shop/ghk-cu/) (PL): GHK-CU 100mg, €40, €0.40/mg
- [XL Peptides](https://xlpeptides.com/product/ghk-cu-50mg/) (GB): GHK-Cu 50mg Research Peptide, €22, €0.43/mg
- [Europa-Peptide](https://europa-peptide.de/en/shop/ghk-cu/) (PL): GHK-CU 50mg, €25, €0.50/mg
- [Baltic Peptides](https://balticpeptides.com/product/ghk-cu/) (LT): GHK-Cu 100mg, €50, €0.50/mg
- [Semax Polska](https://semaxpolska.com/en/ghk-cu-60-mg/) (PL): GHK-Cu, 60 mg, €32, €0.53/mg

## Studies

- [Pickart & Margolina 2018: regenerative and protective actions of the GHK-Cu peptide in the light of the new gene data](https://pubmed.ncbi.nlm.nih.gov/29986520/) (review, 2018): Summarises GHK-Cu's wound-healing, collagen and gene-expression effects; the human evidence it cites is topical cosmetic work, with no trial of injected GHK-Cu.
- [Miller et al. 2006: topical copper tripeptide complex on CO2 laser-resurfaced skin](https://pubmed.ncbi.nlm.nih.gov/16847171/) (rct, n=13, 2006): Topical GHK-Cu after laser resurfacing gave no objective improvement in redness, wrinkles or skin quality over standard care; only patient-rated skin quality favoured it.
- [Canapp et al. 2003: topical tripeptide-copper complex on healing of ischemic open wounds](https://pubmed.ncbi.nlm.nih.gov/14648529/) (animal, n=24, 2003): 2% GHK-Cu gel shrank ischemic wounds in rats faster than vehicle or no treatment (64.5% vs 28.2% area reduction by day 13) and lowered TNF-alpha and MMP-2/9.
- [Bian et al. 2024: GHK-Cu attenuates lung inflammation and fibrosis in silicosis by targeting peroxiredoxin 6](https://pubmed.ncbi.nlm.nih.gov/38879894/) (animal, 2024): GHK-Cu reduced lung inflammation and fibrosis in silicosis mice without significant systemic toxicity, via an antioxidant effect in alveolar macrophages.
- [Mazzola et al. 2026 (preprint): middle-aged mice treated with GHK-Cu intraperitoneally or intranasally](https://doi.org/10.21203/rs.3.rs-9520102/v1) (animal, 2026): In aged mice, 5 days of injected GHK-Cu (15 mg/kg) gave only a transient learning gain in males, while 8 weeks intranasal improved learning in both sexes.

## Sources

- [FDA risk note: GHK-Cu for injectable routes](https://www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks)
- [Pickart & Margolina 2018 review (angiogenic/growth-factor and gene-expression effects)](https://pmc.ncbi.nlm.nih.gov/articles/PMC6073405/)
- [r/Biohacking: GHK-Cu 20 week update](https://www.reddit.com/r/Biohacking/comments/1xg530o/ghkcu_20_week_update_read_the_full_post/)