How to reconstitute GHK-Cu

What adding water actually changes

GHK-Cu is sold as a dried powder sealed under vacuum in a glass vial. It cannot be drawn into a syringe in that state, so it is dissolved in bacteriostatic water first. Bacteriostatic water is sterile water with a preservative added, which is why it is used for vials that will be entered more than once rather than plain sterile water.

The single point that trips up most people: the water volume does not change how much peptide you have. A 50 mg vial contains 50 mg of powder whether you add 1 mL or 3 mL. What the water changes is how much peptide sits in each millilitre of liquid, and therefore how far along the syringe barrel a given dose sits.

That is the whole of the arithmetic. Milligrams in the vial divided by millilitres of water equals milligrams per millilitre. Everything else on this page follows from that one division.

To mix, the water is added slowly down the inside wall of the vial rather than squirted directly onto the powder, and the vial is swirled rather than shaken. This is standard handling practice for lyophilized peptides and is not specific to GHK-Cu.

Reading the concentration table

The table above covers the two vial sizes commonly listed, 50 mg and 100 mg, against the three water volumes most often used, 1 mL, 2 mL and 3 mL. Three things in it are worth pulling out.

First, doubling the water halves the concentration. A 50 mg vial goes from 50 mg/mL at 1 mL to 25 mg/mL at 2 mL. Nothing was lost. The same peptide is spread through twice as much liquid, so each unit of volume carries half as much.

Second, a 100 mg vial in 2 mL lands on exactly the same concentration as a 50 mg vial in 1 mL: both give 50 mg/mL. A given syringe reading therefore means nothing until you know which vial and which water volume produced it. This is why any figure quoted without its inputs is useless, and why every number on this site is written with the vial size and water volume attached.

Third, 3 mL produces awkward numbers. A 50 mg vial in 3 mL gives 16.67 mg/mL and a 100 mg vial in 3 mL gives 33.33 mg/mL. These are repeating decimals rounded for display. If you dislike rounding in your own arithmetic, choosing 1 mL or 2 mL keeps the concentration a whole number and keeps the later division clean.

Turning a concentration into a syringe reading

Listings for GHK-Cu describe amounts in milligrams, commonly 1 mg, 2 mg or 3 mg. A syringe is not marked in milligrams. It is marked in volume, or in insulin units that correspond to a fixed fraction of a millilitre. So the milligram figure has to be converted before it means anything at the barrel.

The conversion is one division followed by one multiplication. Divide the dose in milligrams by the concentration in milligrams per millilitre. That gives the volume in millilitres. Then multiply that volume by the number of units your syringe marks per millilitre, which is printed on the barrel or the packaging. The result is the reading.

Because concentration is the denominator, a more dilute mix pushes the same milligram amount further up the barrel. That is the practical argument for using more water with small doses: the mark you are aiming for is larger and easier to hit accurately. The counterargument is that more water means fewer total doses fit in a vial of fixed volume capacity. Neither is a recommendation from us. It is the tradeoff the arithmetic creates.

What this page does not tell you

We hold no reliable human pharmacokinetic data for GHK-Cu. This site therefore makes no claim about its half life, how quickly it clears, whether it accumulates with repeated administration, or how long any effect might last. If you have seen timing figures for this compound quoted elsewhere, we are not in a position to confirm or contradict them, and we will not repeat them.

GHK-Cu is not approved by any regulator for human use. Nothing here is medical advice, and this page has had no clinical review. It does not tell you what dose to use, what to expect, what adverse effects occur, or whether the compound is safe or effective. Those are questions for a qualified clinician, and they are outside what dose arithmetic can answer.

The milligram amounts referenced above are the amounts that appear in vendor listings. Their presence here is a description of the market, not an endorsement of any of them. The only thing this page does is convert between milligrams in a vial, millilitres of water, and the concentration those two produce.

What we do not know

We hold no reliable human pharmacokinetic data for GHK-Cu, so this site makes no claims about its half life, how long it takes to clear, or how it accumulates. The arithmetic below concerns concentration and volume only.

This page answers arithmetic and handling questions. It does not tell you what dose to take, what to expect, or whether anything is appropriate for you, and there is no medical review behind it.

Common questions

How much bacteriostatic water should I add to a GHK-Cu vial?

There is no single correct volume, because water volume sets concentration rather than dose. The table covers 1 mL, 2 mL and 3 mL against 50 mg and 100 mg vials. Whole-millilitre choices that give whole-number concentrations, such as a 50 mg vial in 1 mL for 50 mg/mL, keep the later arithmetic simple.

Does adding more water mean I am getting less peptide?

No. The vial contains the same mass of powder regardless of how much water you add. More water lowers the concentration, so a given dose occupies more volume on the syringe. The total peptide available from the vial is unchanged.

Can I use regular sterile water instead of bacteriostatic water?

Sterile water contains no preservative, which is the reason bacteriostatic water is the standard choice for vials that will be entered more than once. Whether either is appropriate for your situation is a clinical question, and this page does not answer clinical questions.

Why do the 3 mL rows show repeating decimals?

Because 50 divided by 3 and 100 divided by 3 do not resolve to clean numbers. The table shows 16.67 mg/mL and 33.33 mg/mL as rounded values. If you would rather not carry rounding through your own division, 1 mL or 2 mL gives a whole-number concentration.

How long does GHK-Cu stay in the body?

We do not know, and we will not guess. There is no reliable human pharmacokinetic data for GHK-Cu that this site is willing to stand behind, so we make no claim about half life, clearance or accumulation. This page covers concentration and volume only.

Two different vials gave me the same concentration. Did I make a mistake?

Probably not. A 100 mg vial in 2 mL and a 50 mg vial in 1 mL both give 50 mg/mL, because the ratio is what matters. The difference is total peptide in the vial, not strength per millilitre. Always record which vial and which water volume produced a given mix.