GHK-Cu
Glycyl-L-Histidyl-L-Lysine Copper Peptide
Last updated: April 26, 2026
Also known as: GHK-Copper, Copper Tripeptide-1, Lamin
What It Is
If you’ve heard of GHK-Cu in the context of high-end skincare or hair restoration and want to know what’s actually behind it, here’s the honest version.
GHK-Cu is a tripeptide — three amino acids (glycine, histidine, lysine) — bound to a single copper ion. Your body produces it naturally; levels in human plasma are highest in your twenties and decline significantly by your sixties. That decline correlates with reduced wound-healing capacity, slower skin regeneration, and visible aging — which is why GHK-Cu has been studied as a topical agent for decades.
The compound works through multiple mechanisms: it stimulates collagen and elastin production in skin, accelerates wound healing, modulates inflammation, and signals stem cells in hair follicles. The copper ion is structurally critical — without it, the GHK tripeptide on its own is far less active. Together, they’re one of the most-studied peptide-mineral complexes in cosmetic and clinical research.
A note on how GHK-Cu shows up: The same molecule appears in over-the-counter skincare products (where it’s regulated as a cosmetic ingredient under much lighter FDA rules) and in compounded prescriptions from pharmacies (where it falls under the Category 2 / PCAC framework). This page covers compounded therapeutic use — the prescription pathway. The skincare-aisle path is a separate regulatory universe.
What Does the Research Actually Show?
Topical Skin Aging & Wound Healing
T2: Emerging EvidenceGHK-Cu has the strongest topical evidence base of any peptide on the post-Category 2 list. Multiple human clinical trials have shown improvements in skin firmness, elasticity, fine lines, and photodamage with sustained topical application. Studies on wound healing are similarly positive — accelerated re-epithelialization, increased collagen deposition, reduced scarring. The evidence here meaningfully exceeds the bar typical for compounded peptides. That said: the dose-response relationship, ideal concentration, and long-term outcomes are still being characterized. Most trials run 12 weeks or shorter; few have studied use over years.
Topical Hair Growth & Restoration
T2: Emerging EvidenceGHK-Cu is used in clinical hair restoration as a topical scalp treatment, sometimes paired with minoxidil or finasteride. Clinical studies show increased hair follicle size, prolonged anagen (growth) phase, and improved density with consistent application. Some compounding pharmacies prepare scalp solutions specifically for hair restoration use. The evidence is real but smaller in scale than the skin-aging studies. Effects are gradual — typically 3–6 months before measurable changes — and require consistent ongoing use to maintain.
Injectable for Systemic Anti-Inflammatory & Tissue Repair
T3: Early / AnecdotalThis is where the evidence picture diverges sharply. While topical GHK-Cu is well-supported, injectable use for systemic anti-inflammatory effects, joint repair, or general anti-aging has minimal human clinical data. The injectable case rests on extrapolation from topical and preclinical animal work — not on controlled trials in injectable forms. Practitioners who prescribe injectable GHK-Cu often cite the topical evidence as supporting it, but the routes of administration produce very different pharmacokinetics. What works topically does not automatically work systemically.
It’s worth noting: GHK-Cu’s strong topical evidence has been used to market injectable forms aggressively. The honest read is that topical use has a credible evidence base, while injectable systemic use is essentially unstudied at the clinical-trial level.
How Is GHK-Cu Administered?
| Route | Topical (cream, serum, scalp solution) — most common. Subcutaneous injection — less common, weaker evidence. |
| Dosage Range | Topical: typically 0.1%–3% concentration. Injectable: 1–5 mg per dose. |
| Frequency | Topical: 1–2x daily. Injectable: 1–3x weekly. |
| Cycle Length | Topical: ongoing. Injectable: 4–8 week courses, often cycled. |
| Time to Effect | Topical: 4–12 weeks. Injectable: variable. |
| Note | Your provider determines the right protocol. Do not self-dose. |
Protocols vary by individual. Always follow your prescribing provider's instructions.
For injection supplies and self-administration basics, see our Injectable Peptide Supplies Guide →
What Are the Side Effects and Risks?
- Mild skin irritation, redness, or tingling at topical application sites.
- Injection site reactions for injectable use (mild, transient).
- Possible allergic reactions in copper-sensitive individuals.
- Limited human safety data for long-term injectable use.
- Pregnancy and breastfeeding are absolute contraindications for injectable use.
Who Should NOT Use GHK-Cu?
If you have Wilson’s disease or copper metabolism disorders: GHK-Cu delivers copper to tissues. In Wilson’s disease and related conditions where copper accumulates pathologically, this is contraindicated. Your hepatologist or specialist must be in the loop before any GHK-Cu use, topical or injectable.
If you have a known copper allergy or sensitivity: Topical reactions can range from mild irritation to significant dermatitis. Injectable use in copper-sensitive individuals is unstudied and potentially dangerous.
If you are pregnant or breastfeeding: No safety data exists for injectable GHK-Cu in these populations. Topical use is more likely to be considered acceptable, but this is a conversation with your obstetrician, not a peptide provider.
If you have an active malignancy or recent cancer history: GHK-Cu modulates angiogenesis and tissue regeneration pathways. The interaction with cancer biology is not characterized in humans on GHK-Cu protocols. If you have an active cancer, are in remission, or have a strong family history, this conversation belongs with your oncologist.
If you are self-sourcing from unregulated vendors: GHK-Cu was removed from Category 2 effective April 22, 2026 but is not yet legal to compound. Buying “research peptide” GHK-Cu from unregulated vendors gives you no assurance of purity, sterility, or accurate dosing.
Is GHK-Cu Legal in 2026?
Not FDA-approved as a compounded prescription drug. Removed from Category 2 effective April 22, 2026. PCAC review scheduled for the second of two PCAC meetings, to be held before February 2027 — alongside Melanotan II, LL-37, Dihexa, and PEG-MGF. Compounding cannot resume until after PCAC review and a final FDA determination adds GHK-Cu to the 503A bulks list. If approved, it will be available via prescription through licensed compounding pharmacies — it will NOT be available over the counter or FDA-approved as a drug. Note: GHK-Cu remains widely available as a cosmetic ingredient in over-the-counter skincare, where it operates under a different (much lighter) regulatory framework. The compounded therapeutic pathway and the cosmetic pathway are separate. The FDA accepts public comments through Docket FDA-2025-N-6895. The deadline for GHK-Cu specifically will be set when the second PCAC meeting is scheduled.
This compound’s legal status is actively evolving. Get updates when it changes →
Before You Start: Get Baseline Labs
We recommend baseline lab work before starting any peptide protocol so you and your provider can track changes. Key markers include For topical use, baseline labs are not strictly necessary. For injectable use, if you have any history of copper metabolism issues, ceruloplasmin and serum copper levels should be assessed.
Ask your provider about ordering these labs, or search for direct-to-consumer lab testing services in your area.
Order at-home labs from Everlywell →Lab recommendations are the same regardless of which service you use. See how we make money.
What You'll Need
If your provider prescribes an injectable protocol, you'll need basic supplies.
- Bacteriostatic Water (30ml)Link coming soon
- Insulin Syringes 29 gauge (100ct)Link coming soon
- Alcohol Prep Pads (200ct)Link coming soon
- Sharps ContainerLink coming soon
Supply links are affiliate links. We may earn a commission at no cost to you. We only link to commodity supplies, never to peptide products. See how we make money.
Questions for Your Provider
- 1Based on my specific goal — skin, hair, or systemic — which route of administration do you recommend, and what’s the evidence supporting that choice?
- 2If injectable, what’s the evidence base specifically for injectable GHK-Cu in my use case? Topical evidence does not automatically translate.
- 3What concentration or dose are you prescribing, and how was that determined?
- 4What’s the current compounding availability for GHK-Cu given the post-Category 2 / pre-PCAC limbo? On what legal basis is your pharmacy filling these prescriptions?
- 5Which compounding pharmacy do you use, and is it 503A or 503B?
- 6How will we measure response — visual changes, photography, lab markers, or combination?
- 7What does success look like at 12 weeks, and at what point would we conclude GHK-Cu isn’t working?
How Do I Get GHK-Cu Through a Legitimate Provider?
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