Peptide guide

GHK-Cu

Copper tripeptide-1 — a naturally occurring copper-binding peptide studied for skin, hair, and tissue repair.

GHK-Cu is a small copper-carrying peptide your own plasma makes, and its level drops sharply as you age. The version sold here is the injectable: powder in a vial you reconstitute and inject under the skin, studied for skin, hair, and wound repair. It also has a long life as a cosmetic cream ingredient. The injectable evidence is mostly cell-culture and animal work, with almost nothing in completed human injection trials, while the topical research is more developed. It isn't FDA-approved as a drug. The useful questions are how to handle it, why the solution turns blue, and how to tell a real source from a scam.

By the Zapify Research team

Reviewed against 9 clinical & research sources · Updated June 2026 · Educational use only

Type: Copper tripeptideGly-His-Lys + Cu²⁺
Route: Subcutaneous
Typical dose: 1–2 mg/day subQinjected under the skin
Cycle: ~30 days onthen a break
Storage: Mixed: ~4 wksSealed: months
Status: Not FDA-approved

What is GHK-Cu?

A three-amino-acid peptide holding one copper atom that your own plasma makes — levels fall from ~200 to ~80 ng/mL by 60, and the injectable isn't FDA-approved.

GHK-Cu is a tiny peptide carrying a copper ion. The peptide part, GHK, is just three amino acids: glycine, histidine, and lysine. That short chain grabs a single atom of copper and holds it, and the pair together is what does the work. The copper isn't an additive or a contaminant; it's the active half of the molecule.

Pickart first isolated it from human blood plasma in 1973, which makes it unusual in this category: your body already makes it. Plasma levels run around 200 ng/mL at age 20 and fall to roughly 80 ng/mL by age 60. That age-related decline is a large part of why people are interested in putting it back.

It shows up in two forms that get talked about as if they're one thing. Injectable GHK-Cu is the powder-in-a-vial version people reconstitute and inject under the skin, and it's what this guide and the calculator are built around. Topical GHK-Cu has been a skincare ingredient for decades, sold in serums and creams. They share a molecule, not an evidence base.

GHK-Cu isn't FDA-approved as a drug for anything. The injectable form has never been through the drug-approval process, and no pharmaceutical sponsor has pursued one. In a cream, it's regulated as a cosmetic ingredient, which doesn't require drug approval and doesn't mean it's been proven to treat anything. Treat the injectable as an experimental research compound, not a medicine.

What is it studied for?

Fifty years of papers, but almost all topical or lab work — controlled human trials of the injected form for skin, hair, or healing are essentially absent.

GHK-Cu has a longer paper trail than most peptides in this space — fifty years of it — but the depth is uneven. The topical and lab work is genuinely substantial. Controlled human trials of injected GHK-Cu for skin, hair, or healing are essentially absent, so the injectable claims lean on cell-culture studies, animal models, and the topical results stretched to a route they weren't tested on.

Evidence base, by setting

DecadesLab, animal & topical studies

NoneHuman injection trials

The research has clustered in three areas:

Skin & collagenStimulating collagen, elastin, and the glycosaminoglycans that keep skin firm and hydrated. This is the best-supported use and where the cosmetic data lives.

Wound & tissue repairFaster wound closure, new blood-vessel growth, and less scarring in animal and lab models. Some chronic-wound interest, including diabetic ulcers.

Hair folliclesEnlarging follicles and improving scalp blood supply. A few small studies compare it favorably to minoxidil, though the trials are limited.

Why it does so much at once is the interesting and unsettled part. A Connectivity Map analysis run through the Broad Institute found GHK shifts the expression of roughly a third of human genes — about 31% changed by 50% or more — rather than hitting one receptor. The leading reading is that it acts as a broad signal that nudges damaged tissue back toward a repair-and-rebuild program. How reliably an injected dose reproduces that in a living body, versus what a cream does in skin, is still open.

Why people use it

People chase skin aging, hair thinning, and wound healing on the strength of lab, animal, and topical data, but no human trial shows injected GHK-Cu does any of it.

Most people who reach for GHK-Cu fall into one of a few situations. These are the reasons they try it, not evidence that it delivers:

Skin aging — fine lines, loss of firmness, dullness — drawn by the collagen and elastin work, where the cosmetic research is strongest.
Hair thinning, drawn by the early follicle and scalp-circulation work and the handful of minoxidil comparisons.
A slow-healing wound or surgical recovery, hoping to borrow the angiogenesis and collagen effects seen in animal models.
The idea of replacing something the body makes less of with age, since plasma levels measurably fall over the decades.

No human trial has shown that injected GHK-Cu will do any of this. What's there is fifty years of lab and animal work, a coherent mechanism, decent topical skin data, and a mild reported side-effect profile. The injectable vial is worth being curious about and isn't enough to rely on, and none of it replaces the basics with real evidence: sun protection, sleep, and, for hair, the treatments that have been through trials.

How to reconstitute GHK-Cu

Mix with bacteriostatic water (saline strips the copper), swirl don't shake, and expect a clear blue solution — the copper, not contamination.

The injectable version arrives as a small puck of dry powder. Before you can use it, you mix it into a liquid. That step is called reconstitution, and it's the same process used for most research peptides, with one quirk specific to this one.

Step 1Start with powderWipe the rubber stopper with an alcohol swab.

Step 2Add bac. waterRun it slowly down the inside wall — never shake.

Step 3Draw your doseThe calculator gives the exact units to draw to.

Wipe the rubber stopper with an alcohol swab first, every time.
Use bacteriostatic water, not plain sterile water and not saline. The trace of benzyl alcohol in it holds back bacteria, which matters because you'll be drawing from the same vial for weeks; saline is a separate problem, since its salt can strip copper from the peptide.
Add the water slowly, running it down the inside glass wall. Don't blast it straight onto the powder.
Don't shake it. Roll or swirl gently and let it dissolve on its own, which usually takes a couple of minutes. Shaking foams the solution and can damage the peptide.

The solution turns a clear blue once it dissolves. That's the copper, and it's the normal, expected look for this compound — not contamination or a spoiled vial. A common setup is a 50 mg vial mixed with 5 mL of bacteriostatic water, which gives 10 mg/mL. On a U-100 insulin syringe, 20 units is then 2 mg. The water doesn't change how much peptide is in the vial; it only sets the concentration, which decides how many units you draw for the subcutaneous injection. More water means a more dilute mix and a bigger draw for the same dose. You only change the draw math, and that's exactly what the calculator handles.

Calculate your exact GHK-Cu reconstitution →

Dose & units

No FDA-approved dose; clinics report 1–2 mg a day, often five days a week, cycled around 30 days on and two weeks off to limit copper buildup.

There is no FDA-approved dose for GHK-Cu. Everything below is a range that clinics and write-ups report, not a medical standard. Because GHK-Cu carries copper, the dose is also a copper dose, which is its own reason not to freelance the numbers. Decide what goes into your body with a licensed provider, not with this page.

Typical range

Injected under the skin, the range reported most often is 1–2 mg per day, often five days a week. Lower end for skin; the higher end shows up in wound-healing and hair write-ups. (For reference, the copper riding along on a 2 mg dose is only a fraction of a milligram — well under both the daily dietary requirement and the tolerable upper limit — but it stacks up across a course.)

Titration

Most people begin near the low end, around 1 mg a day, and hold there before adjusting. Starting low lets you notice any reaction, including the flushing some report, before committing to more.

Cycling

Sources treat this as a time-limited course rather than something to run continuously, partly to keep cumulative copper in check. A commonly reported pattern is about 30 days on, then roughly two weeks off before repeating.

On~30 days

Off~2 weeks

For the exact mark to draw to on your insulin syringe, don't eyeball it. The calculator turns your vial size, water, and dose into the precise number of units for the subcutaneous draw.

Get your exact units →

Storage

Sealed powder lasts months at room temperature; once mixed, refrigerate at 2–8 °C and use within about 4 weeks — a contamination limit, not potency.

Sealed & dryDry powder stays stable for months and shrugs off shipping heat; many sources keep the lyophilized powder cold for longer-term holding.

ReconstitutedRefrigerate at 2–8 °C in the main compartment, use within about 4 weeks, don't freeze, keep out of light, and toss if cloudy or off-color.

You'll see longer windows quoted for peptide vials. Those figures are beyond-use dates for a sealed, unmixed vial that a compounding pharmacy has stability-tested, and they stop applying the moment you add water. A mixed vial runs on the roughly four-week clock instead, because that's how long the preservative in bacteriostatic water reliably keeps the solution clean once you're drawing from it.

That four-week limit is about contamination, not potency — the peptide often stays good well beyond it. The blue color is normal and not a spoilage cue; cloudiness, particles, or a color shift away from clear blue are. Reconstitute with plain sterile water instead of bacteriostatic and you drop to a day or two, since there's no preservative holding bacteria back.

Don't freeze a reconstituted vial, keep it out of direct light, write the mix date on the label, and throw it out if the solution ever turns cloudy or discolored, whatever the date says.

Side effects & safety

Reported effects are mild injection-site redness and occasional flushing, but each shot adds copper, so it's off-limits in Wilson's disease and not for indefinite use.

The reported side effects are generally mild. That picture comes from topical use, animal studies, and scattered clinic observation, not large human safety trials of the injectable, so hold it loosely.

Most common: mild, short-lived redness, itching, or irritation right at the injection site, usually settling within a day or two.
Less often: brief warmth or flushing in the face or body within about half an hour of a dose, reported by a small share of users.

The dose-specific caution here is copper. Each injection delivers copper along with the peptide, and it accumulates across a cycle, so this isn't for anyone with a copper-metabolism disorder like Wilson's disease, and it's a reason to respect cycling and not run it indefinitely. Talk to a doctor first if you have any condition affecting copper handling, the liver, or the kidneys, and if you're pregnant or breastfeeding.

On anti-doping: GHK-Cu is not named on the WADA Prohibited List. That isn't a guarantee of clearance, since WADA bans some substances by class and function rather than by name, and a tested athlete carries that risk. If you compete, check with your sport's anti-doping authority rather than assuming.

And the biggest risk here isn't really the molecule. It's whether what's in the vial is actually GHK-Cu, at the strength on the label, with the copper actually bound. That comes down to where you buy it.

How to vet a source

A batch-specific, third-party COA whose lot number matches your vial is the one document separating a real seller from a gamble — and it should confirm the copper is bound.

This is an unregulated market, and a real share of independently tested vials come back underdosed, impure, or not even the compound on the label. With GHK-Cu there's an extra wrinkle: the copper has to be properly complexed to the peptide for the molecule to behave as intended, and you can't confirm that from the powder. Where you buy matters more than almost anything else here. The one document that separates a real seller from a gamble is a certificate of analysis: a third-party lab's report on what's actually in the vial.

A real COA shows

An identity test (usually mass spectrometry) confirming the peptide is what the label says.
A purity figure from HPLC, typically 98% or higher.
A lot or batch number that matches the number printed on your vial.
A named, independent accredited lab and a recent test date.

Walk away if

There’s no COA, or it’s a generic image with no lot number.
The “certificate” comes from the seller instead of a third-party lab.
The lot number doesn’t match your vial, or there isn’t one at all.
It’s a flat image you can’t trace back to the lab that issued it.

That's the standard worth holding any seller to, ours included. Ask for the batch-specific COA before you buy, match the lot number to your vial, and don't accept a screenshot in place of a traceable report.

See the Zapify compound catalog →

Common questions about GHK-Cu

Is GHK-Cu approved or proven to work in people?

Not as a drug. It isn't FDA-approved for any therapeutic use, and there are essentially no completed human trials of the injectable form. In a cosmetic cream it's a regulated skincare ingredient, which is a different and lower bar than drug approval — it allows the product to be sold, not a claim that it treats anything. The strongest human-relevant data is topical skin research; the injectable claims lean on lab and animal work.

Why does the solution turn blue?

That's the copper. GHK-Cu carries a copper ion as part of the active molecule, and once the powder dissolves the solution takes on a clear blue tint. It's the normal, expected look for this compound, not a sign of contamination or a bad vial. What you don't want to see is cloudiness, floating particles, or a color that's drifted away from clear blue.

How do I run the injectable protocol?

The injectable is the form this site is built around: reconstitute the vial with bacteriostatic water, then inject 1–2 mg subcutaneously, commonly five days a week on a roughly 30-days-on cycle, with the calculator handling your exact units. It's the route people use chasing whole-body or hair effects, and the one that delivers systemic copper, so start low and involve a licensed provider. A licensed provider is the right person to weigh your situation.

Should I worry about copper toxicity?

It's the right thing to ask about. The copper bound to GHK-Cu is a minority of its weight, so a typical 1–2 mg dose delivers only a fraction of a milligram of copper — within the range of normal dietary intake and under the tolerable upper limit. The catch is that it accumulates across a cycle, which is part of why sources cap courses at around 30 days rather than running it forever. Anyone with a copper-metabolism disorder such as Wilson's disease should avoid it, and the load is a reason to involve a provider rather than self-dose indefinitely.

Why bacteriostatic water and not saline or sterile water?

Because you'll be drawing from the same vial across weeks. Bacteriostatic water carries a trace of benzyl alcohol that holds back bacteria between draws; plain sterile water and saline have no preservative. Saline is doubly wrong here, since its salt can pull copper off the peptide. On a multi-dose peptide vial, the professional sources all point the same way: bacteriostatic.

References

This page is for research and educational purposes only. It is not medical advice or a recommendation to use any compound. The dose ranges shown are reported by clinics and research literature, not validated medical standards, and GHK-Cu is not FDA-approved. Talk to a licensed medical provider about anything you put in your body.