GHK-Cu Reconstitution: Water per 50 and 100 mg Vial, Units

How 50 mg and 100 mg GHK-Cu vials convert to mg/mL and U-100 units at 1 to 5 mL of water, for the 1 to 2 mg figures clinic and protocol pages state.

Medibact Guides · Published 2026-09-18

Illustration: Two clear glass vials, one with powder, one with water, on a white lab bench. — Illustration

GHK-Cu is a copper peptide: the tripeptide glycine-histidine-lysine carrying a copper ion, a sequence found in human plasma and used for decades as a cosmetic ingredient. As a research powder it is sold in 50 mg and 100 mg vials, the sizes the GHK-Cu calculator is built around, because the figures in circulation for the injectable form are milligrams a day. This page reports the water volumes the sources state, the concentration each produces, and what the milligram amounts those sources quote come to on a U-100 syringe. It reports and does not recommend. The figures and where each comes from are on the GHK-Cu dosage page; every compound's arithmetic is indexed on the reconstitution hub.

What the sources state

Two facts frame everything below: the injectable figures are milligrams, and no human study has ever injected the peptide.

Source	What it states	Kind of source	Opened
DailyMed search, "GHK-Cu"	One record, a sunscreen cream listing the peptide as a cosmetic ingredient; no injection	Regulator database	2026-09-18
ClinicalTrials.gov, GHK-Cu as intervention	Three records: a topical gel for wound healing (NCT07437586, Phase 2, recruiting), a patch's effect on circulating GHK (NCT07706361, not yet recruiting), a facial-skin study of three products (NCT05932732, Phase 4, completed); none injects it	Trial registry	2026-09-18
PubMed	80 records for GHK-Cu; two with injection or subcutaneous terms in human-tagged records, a 2026 biomaterials paper and a 2026 narrative review, neither a trial	Literature database	2026-09-18
Peptide Dosing Protocols, GHK-Cu guide	50 mg in 2.0 mL, 25 mg/mL, "a 1 mg draw (U-100) 0.04 mL = 4 units"; 100 mg in 5.0 mL, 20 mg/mL, 1 mg is 5 units; "1-2 mg per day SubQ for a 4-8 week cycle"; "No published human randomized trial has evaluated injectable GHK-Cu"	Protocol site, last reviewed August 2026	2026-09-18
Perfect B clinic page	50 mg in 2 mL, 25 mg/mL, "0.25 mg per unit"; 1 mg (4 units) a day for days 1 to 15, 2 mg (8 units) for days 16 to 30, subcutaneously before bed	Clinic page, updated for 2026	2026-09-18

The two pages agree on the configuration and on the range, and both are conventions: there is no label and no trial for either to rest on. The protocol page says so itself.

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Water per vial and the concentration it gives

The calculator works every vial at 1, 2 and 3 mL; the sources add 5 mL. One U-100 unit is a hundredth of a millilitre (MedlinePlus, "Giving an insulin injection", reviewed 2024-07-21), so the micrograms in a unit are the concentration in mcg/mL divided by 100.

Vial	Water added	Concentration	Micrograms per unit
50 mg	1 mL	50 mg/mL	500 mcg
50 mg	2 mL	25 mg/mL	250 mcg
50 mg	3 mL	16.7 mg/mL	167 mcg
50 mg	5 mL	10 mg/mL	100 mcg
100 mg	2 mL	50 mg/mL	500 mcg
100 mg	3 mL	33.3 mg/mL	333 mcg
100 mg	5 mL	20 mg/mL	200 mcg
100 mg	10 mL	10 mg/mL	100 mcg

The 50 mg in 2 mL row is both sources' configuration; the 100 mg in 5 mL row is the protocol page's. A 100 mg vial in 10 mL and a 50 mg vial in 5 mL are the same solution, with twice the number of draws in the larger vial.

The stated milligram amounts in syringe units

The pages state 1 mg and 2 mg a day, and the protocol page's middle tier is 1 to 1.5 mg. Each row is one of the concentrations above.

Concentration	1 mg	1.5 mg	2 mg
50 mg/mL (50 mg in 1 mL, 100 mg in 2 mL)	2 units	3 units	4 units
25 mg/mL (50 mg in 2 mL)	4 units	6 units	8 units
20 mg/mL (100 mg in 5 mL)	5 units	7.5 units	10 units
16.7 mg/mL (50 mg in 3 mL)	6 units	9 units	12 units
10 mg/mL (50 mg in 5 mL, 100 mg in 10 mL)	10 units	15 units	20 units

Every cell is a small fraction of a 100-unit barrel. That is the opposite of the milligram-scale problem the NAD+ page has, where the draws overflow the syringe; here the vial is large but the amounts are still small enough that the difficulty is reading them.

Why the draw is small and what more water does

At 25 mg/mL a 1 mg amount is a 4-unit draw. The graduations on a U-100 syringe are single units, so a half-unit misreading is 12.5% of the amount. At 10 mg/mL the same milligram is 10 units and the same misreading is 5%. That is the whole reason some pages choose 5 mL rather than 2 mL, and it is a statement about measurement resolution, not about the amount itself.

What more water does not do is change the vial's contents. A 50 mg vial holds fifty 1 mg amounts or twenty-five 2 mg amounts at 1 mL, 2 mL or 5 mL; a 100 mg vial holds twice as many. At the 30-day schedule the clinic page describes, 15 days at 1 mg and 15 at 2 mg is 45 mg, which is why that page's cycle fits one 50 mg vial. That is arithmetic about a stated schedule, not a comment on the schedule.

The mixing steps, as the clinic page and a label describe them

GHK-Cu has no label to quote, and the clinic page is unusually specific about the procedure, so both descriptions are given. The clinic page: the tops of the peptide vial and the water vial are wiped with an alcohol swab; 2 mL of bacteriostatic water is drawn with a 3 mL syringe; the water is directed toward the inner wall of the vial, not onto the powder; the vial is rolled gently between the palms until the powder has dissolved, never shaken; the vial then goes into the refrigerator. The labelled version of the same steps, from the EGRIFTA WR (tesamorelin) prescribing information revised in March 2025 for a lyophilized peptide supplied with bacteriostatic water: the stated diluent volume is added, the vial is moved in a circle to mix and is not shaken, and the solution is inspected and used only if clear and free of particles. The general procedure for any lyophilized vial is on Medibact's how to reconstitute peptides page and is not repeated here.

Storage after mixing

There is no GHK-Cu label to quote on the solution's storage; what labels and manufacturers state about reconstituted peptides is on Medibact's how to store peptides page.

What this page does not do

It does not state an amount of GHK-Cu to use, a route, a schedule or a cycle. The 1 mg and 2 mg figures are reported because a clinic page and a protocol page state them, and the protocol page's own words are that no published human randomized trial has evaluated injectable GHK-Cu; the registry and the literature confirm that the human evidence is topical. The arithmetic converts stated inputs exactly and says nothing about whether any input is appropriate. Medibact's GHK-Cu guide covers the compound; Peptifact's GHK-Cu dosage page keeps the topical trials and the injectable conventions apart. Decisions about administering anything to a person belong with a clinician.

Sources and dates

Opened 2026-09-18: the DailyMed SPL search API for "GHK-Cu" (one record, a cosmetic cream); the ClinicalTrials.gov v2 API for GHK-Cu as an intervention (three records: NCT07437586, NCT07706361, NCT05932732); PubMed through the NCBI E-utilities for "GHK-Cu"[tiab] (80 records) and for "GHK-Cu"[tiab] AND (injection OR subcutaneous) AND humans[mh] (two records, PMID 42320090 and PMID 41476424, both summaries read); the Peptide Dosing Protocols GHK-Cu guide (last reviewed August 2026); the Perfect B GHK-Cu protocol page (updated for 2026); the EGRIFTA WR prescribing information (revised 3/2025, section 2.2); MedlinePlus, "Giving an insulin injection" (reviewed 2024-07-21). Corrections go to the contact page.

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Medibact Guides facts

GHK-Cu is the tripeptide glycine-histidine-lysine bound to a copper ion. Research vials are 50 mg and 100 mg, the two sizes the calculator carries, five to ten times the mass of a typical peptide vial, because the figures in circulation are milligrams a day rather than micrograms.
No injectable GHK-Cu product has a label anywhere: a DailyMed search for GHK-Cu on 2026-09-18 returned one record, a sunscreen cream listing the peptide as a cosmetic ingredient, and no injection.
ClinicalTrials.gov held three GHK-Cu intervention records on 2026-09-18: a Phase 2 study of a topical gel for wound healing (NCT07437586, recruiting), a study of a wearable patch's effect on circulating GHK levels (NCT07706361, not yet recruiting) and a completed Phase 4 facial-skin study of three products (NCT05932732). None injects the peptide.
PubMed held 80 records with GHK-Cu in the title or abstract on 2026-09-18. Restricting to injection or subcutaneous terms in human-tagged records returned two: a 2026 biomaterials paper on GHK-Cu grafted onto bone-repair microspheres and a 2026 narrative review for orthopaedic physicians. Neither is a study of injected GHK-Cu in people.
The figures clinic and protocol pages state are 1 to 2 mg subcutaneously per day: a protocol page describes 1 to 2 mg per day for a four- to eight-week cycle and states that no published human randomized trial has evaluated injectable GHK-Cu (Peptide Dosing Protocols, last reviewed August 2026); a clinic page describes 1 mg a day for days 1 to 15 and 2 mg a day for days 16 to 30 (Perfect B, updated for 2026); both opened 2026-09-18.
Both pages work a 50 mg vial in 2 mL of bacteriostatic water, 25 mg/mL, on which one U-100 unit carries 250 mcg, so 1 mg is 4 units and 2 mg is 8; the protocol page also works a 100 mg vial in 5 mL, 20 mg/mL, on which 1 mg is 5 units.
At the calculator's 1, 2 and 3 mL a 50 mg vial gives 50, 25 and 16.7 mg/mL, so a 1 mg amount is 2, 4 and 6 units; at 5 mL it is 10 mg/mL and 10 units. A 100 mg vial at the same volumes is twice as concentrated, and the draws halve.
A 50 mg vial holds fifty 1 mg amounts or twenty-five 2 mg amounts at any water volume; the water sets the draw, not the count. At 25 mg/mL the whole vial is 2 mL, and the 1 mg draw is a 4-unit reading on which a half-unit error is 12.5% of the amount.
The clinic page describes the mixing as: both vial tops wiped with alcohol, 2 mL of bacteriostatic water drawn with a 3 mL syringe and injected slowly toward the inner wall of the vial rather than onto the powder, the vial rolled gently without shaking, then refrigerated.

Frequently asked questions

How much water goes into a 50 mg vial of GHK-Cu?

No label sets it. The clinic page and the protocol page opened on 2026-09-18 both use 2 mL of bacteriostatic water, which gives 25 mg/mL; the protocol page works a 100 mg vial at 5 mL, 20 mg/mL, and a search of vendor pages the same day showed 5 mL in a 50 mg vial, 10 mg/mL, as a common alternative. The calculator's 1, 2 and 3 mL columns give 50, 25 and 16.7 mg/mL. The volume decides the size of each draw; the 50 mg in the vial does not change.

How many units is 1 mg of GHK-Cu on an insulin syringe?

Four units at 25 mg/mL, which is the 50 mg in 2 mL configuration both pages use. Two units at 50 mg/mL (50 mg in 1 mL, or 100 mg in 2 mL). Five units at 20 mg/mL (100 mg in 5 mL). Six units at 16.7 mg/mL (50 mg in 3 mL). Ten units at 10 mg/mL (50 mg in 5 mL). A 2 mg amount is double each of those. The unit figure has no meaning without the water volume that produced it.

Why are GHK-Cu vials 50 mg and 100 mg?

Because the figures in circulation are milligrams a day, not the micrograms most peptides are discussed in, and a 5 mg vial would hold five days' worth at the pages' lower figure. A 50 mg vial holds fifty 1 mg amounts or twenty-five 2 mg amounts, and a 100 mg vial twice that, whatever water is added. The larger mass also means the powder takes more water to dissolve than a 5 mg vial, which is part of why the pages settle on 2 to 5 mL.

Is there a human study of injected GHK-Cu?

None that could be found. PubMed's 80 GHK-Cu records include human topical work, but restricting to injection or subcutaneous terms in human-tagged records returns a biomaterials paper and a narrative review, not a trial. The three registered studies are a topical gel, a patch and a facial-skin study. The protocol page says the same in its own words: no published human randomized trial has evaluated injectable GHK-Cu, and most clinical evidence is topical.

Does adding more water change how much GHK-Cu the vial delivers?

No. It changes how many units each milligram occupies and therefore how readable the draw is. At 25 mg/mL a 1 mg amount is 4 units, and a half-unit reading error is an eighth of the amount; at 10 mg/mL the same milligram is 10 units and the same error is a twentieth. That is the arithmetic behind the 5 mL configurations some pages use. It is a statement about measurement resolution, not about which amount is appropriate.

How is GHK-Cu reconstituted, according to the clinic page?

The clinic page describes wiping the tops of both vials with alcohol, drawing 2 mL of bacteriostatic water with a 3 mL syringe, injecting it slowly toward the inner wall of the vial rather than directly onto the powder, rolling the vial gently between the palms until the powder is dissolved, and refrigerating it without freezing. That matches what lyophilized-peptide labels describe. Medibact's reconstitution page carries the general procedure; this page carries the arithmetic.