GHK-Cu is dosed two ways that have nothing to do with each other, and the search term "ghk-cu dosage" does not say which one is meant. The topical route has the human evidence: a cream after laser treatment, a scalp formulation, and a 2026 wound-healing trial of a 0.1% gel. The injectable route has vendor pages stating 1 to 2 mg a day and no human study at any dose. This page reports both as their sources state them, keeps them apart, and works the units for the 50 mg and 100 mg vials the site's calculator uses.
GHK-Cu is glycyl-L-histidyl-L-lysine bound to a copper(II) ion, a tripeptide first isolated from human plasma and studied for wound repair and skin remodelling. Medibact's GHK-Cu guide covers the molecule, its half-life and its evidence; this page stays with figures. The dosage hub lists every compound's page, and Peptifact's GHK-Cu dosage page grades the same sources from a journalist's angle.
What the sources state
| Source | Kind | Route | Figure | Date read |
|---|---|---|---|---|
| DailyMed search, "copper tripeptide" | Label search | Any | Four records, all cosmetic (two serums, two mask packs); no drug, no injectable | 2026-09-18 |
| NCT07437586, Hudson Biotech, phase 2, started 2026-02-02, recruiting | Trial protocol | Topical gel | 0.1% w/w GHK-Cu gel, a thin film of about 0.5 g once daily for 14 days, against vehicle on the paired wound; 60 healthy adults planned; primary outcome days to re-epithelialisation | 2026-09-18 |
| Miller et al., Archives of Facial Plastic Surgery 2006 (PMID 16847171) | Trial publication | Topical cream | Copper tripeptide cream after CO2 laser resurfacing; 13 patients; better satisfaction, no objective improvement; concentration not in the abstract | 2026-09-18 |
| Kapoor, Journal of Cosmetic and Laser Therapy 2018 (PMID 29482481) | Case series | Intradermal (scalp) | Growth-factor formulation containing copper tripeptide-1; 8 sessions; 1,000 patients; no dose in the abstract | 2026-09-18 |
| Wang et al., Skin Research and Technology 2026 (PMID 42573538) | Study with a clinical component | Topical | Ferment extract with GHK-Cu; concentration not in the abstract | 2026-09-18 |
| Deng et al., Journal of Cachexia, Sarcopenia and Muscle 2023 (PMID 36905132) | Animal study with human samples | Systemic (mice) | 0.2 and 2 mg/kg in mice; human COPD muscle examined, not dosed | 2026-09-18 |
| Hostynek et al., Inflammation Research 2011 (PMID 20721598) | In vitro skin study | Topical (excised skin) | 0.68% aqueous copper tripeptide; 136 micrograms of copper per square centimetre permeated in 48 hours | 2026-09-18 |
| Vendor and protocol page A | Commonly cited | Subcutaneous | 1 to 2 mg a day; 1 mg, 1 to 1.5 mg and 1.5 to 2 mg tiers; daily or 5 days on and 2 off; 4 to 8 weeks; "not trial-validated"; 50 mg vial at 2 mL | 2026-09-18 |
| Vendor and protocol page A | Commonly cited | Topical | 1 to 2% for the face, 1 to 3% for the scalp, once or twice daily, 8 to 12 weeks | 2026-09-18 |
| Vendor and protocol page B | Commonly cited | Subcutaneous | 1 mg a day in week 1, then 1 to 2 mg a day, up to 3 mg for injury recovery; 8 to 12 weeks then 4 to 6 off; 10 mg vial at 2 mL | 2026-09-18 |
The table has a shape worth noticing. Every row with a human in it is topical or intradermal; every subcutaneous row is a vendor page. The mouse study is the only systemic dosing in the literature, and it is a muscle study, not a skin one.
What a topical percentage is in milligrams
A percentage on a gel or cream is weight for weight: 0.1% is 1 mg of GHK-Cu per gram of product, 1% is 10 mg per gram and 3% is 30 mg per gram. The 2026 trial's thin film of about 0.5 g is therefore about 0.5 mg of GHK-Cu on the wound each day; a 1% serum applied at the same weight would be 5 mg. How much of that crosses the skin is a separate question that the in vitro work answers only for excised skin under a diffusion cell, in micrograms of copper per square centimetre over two days. None of those numbers becomes an injected milligram by any arithmetic, and the trial did not ask them to.
Units per dose at each research-vial size
Research-market GHK-Cu is supplied in 50 mg and 100 mg vials, larger than most peptides because the amounts handled are milligrams. The table takes each at 1, 2 and 3 mL, states the concentration, and converts the vendor figures, 0.5, 1, 2 and 3 mg, into U-100 syringe units, where 100 units is 1 mL (MedlinePlus, read 2026-09-18); the site's insulin syringe units page covers the syringe reading itself.
| Vial | Water added | Concentration | 0.5 mg | 1 mg | 2 mg | 3 mg |
|---|---|---|---|---|---|---|
| 50 mg | 1 mL | 50 mg/mL | 1 | 2 | 4 | 6 |
| 50 mg | 2 mL | 25 mg/mL | 2 | 4 | 8 | 12 |
| 50 mg | 3 mL | 16.7 mg/mL | 3 | 6 | 12 | 18 |
| 100 mg | 1 mL | 100 mg/mL | 0.5 | 1 | 2 | 3 |
| 100 mg | 2 mL | 50 mg/mL | 1 | 2 | 4 | 6 |
| 100 mg | 3 mL | 33.3 mg/mL | 1.5 | 3 | 6 | 9 |
The draws are small because the vials are large: a 100 mg vial at 1 mL makes 1 mg a single unit, the smallest mark on the syringe, and even at 3 mL the 1 mg draw is 3 units. That is the reverse of the microgram peptides, where the problem is a draw too large to fit, and it is why a vendor page working from a 10 mg vial shows 20 units for the same milligram. A 50 mg vial holds fifty 1 mg amounts and a 100 mg vial a hundred, at any water volume. The GHK-Cu calculator works any combination entered; the site's GHK-Cu reconstitution page covers water volumes per vial and the mixing steps as references describe them.
What the figures omit
The trial figure carries a population (healthy adults with a standardised wound), a route, a concentration, a daily frequency and a 14-day duration, and it has no result yet. The older human rows carry a route and a population and no dose. The vendor figures carry a route, a frequency, a tiered titration and a course of 4 to 12 weeks, none of it from a study; one of the pages says so. Neither set says anything about copper: every milligram of GHK-Cu carries its copper ion with it, and no source in the table addresses what repeated injected copper does, because nobody has injected it into a person in a study.
What this page does not do
This page reports figures with their sources and dates and converts the injectable ones into syringe units at the site's vial sizes. It does not recommend a dose, a route, a concentration, a frequency or a course for anyone, does not say whether the vendor convention works, and does not turn it into advice. The mixing steps and the storage of a mixed vial are the store's topics: how to reconstitute peptides and how to store peptides on medibact.com.
Sources and dates
Opened 2026-09-18: the DailyMed SPL search API for "copper tripeptide" (four cosmetic records); the ClinicalTrials.gov v2 API for GHK-Cu, copper peptide and copper tripeptide (three records; NCT07437586 opened in full); PubMed through the NCBI E-utilities for the human-tagged census (56 records) and the abstracts of PMIDs 8747089, 15655171, 16847171, 17603859, 18350235, 25690343, 28370978, 29482481, 20721598, 36905132, 42573538 and 11176716; two vendor and protocol pages (two further pages were blocked and not read); and MedlinePlus for the U-100 definition. Corrections go to the contact page.