Research

GHK-Cu in hair research

What hair studies involving GHK or copper tripeptide actually tested: mostly multi-ingredient products, one GHK complex trial, and no GHK-Cu-only trial.

By the GHK-Cu Peptide editorial team · Last reviewed November 11, 2026 · Editorial review: pending

Short answer

No hair study of GHK-Cu on its own is indexed. The only placebo-controlled study used a complex of copper-free GHK with 5-aminolevulinic acid in 45 men [Lee 2016]. The rest tested products in which copper tripeptide was one of several actives, without control groups [Kapoor 2018] [Patel 2024].

What each hair study tested

5-ALA–GHK complex vs placebo, six months, 45 men: hair-count change differed from placebo in the lower-strength group; hair length and thickness did not differ, and no adverse events were reported [Lee 2016]. The substance was not GHK-Cu.
Intradermal multi-ingredient formulation, 1,000 people, no control group: growth factors, thymosin β4 and copper tripeptide-1 together [Kapoor 2018].
Clinic series of 18,918 men: a regimen that also included approved oral and topical drugs; copper tripeptide was one ingredient of one component [Tanaka 2018].
Scalp scrub plus serum, 15 days, open label: flaking, hydration, density and thickness measured for a two-product regimen [Patel 2024].
Animal and cell study of an injectable multi-ingredient formulation [Kapoor 2020].

Evidence gaps

No randomised, controlled study of GHK-Cu alone on hair.
No study separating the copper peptide’s contribution from the other actives in the products tested.
A 2026 systematic review graded hair formulations by product; GHK appears only within combinations [Joerg 2026].

All hair records

Primary hair research records involving GHK or copper tripeptide
Study	Model and route	What was measured	Limitations	Grade
Patel 2024 Cureus Hair research · Skin research	Humantopical Adults with mild-to-moderate scalp flaking Multi-ingredient product · n = Not reported in the abstract	The study measured adherent scalp flaking, scalp hydration, hair density and hair thickness over 15 days of a two-product regimen.	No control group; 15 days; two products and several actives, so no attribution to the copper peptide.	Evidence grade B
Kapoor 2020 Plast Reconstr Surg Glob Open Hair research · Safety and tolerability data · Non-topical routes	Animalintradermal Human keratinocyte and fibroblast assays; animal hair-growth model Multi-ingredient product	The study measured cytotoxicity of each ingredient in keratinocyte and fibroblast assays and hair growth after intradermal injection of the full formulation in animals.	Multi-ingredient; authors connected to the formulation; abstract truncated in PubMed.	Evidence grade C
Kapoor 2018 J Cosmet Laser Ther Hair research · Non-topical routes	Humanintradermal Adults with hair loss Multi-ingredient product · n = 1000	The study assessed hair regrowth and adverse events after repeated intradermal scalp injections of a multi-ingredient formulation.	No control group; at least six actives, so no effect or safety finding can be attributed to copper tripeptide-1.	Evidence grade B
Tanaka 2018 J Clin Aesthet Dermatol Hair research · Non-topical routes	Humanintradermal Men treated in one clinic, 2011–2017 Multi-ingredient product · n = 18,918 treated	The series assessed pre- and post-treatment photographs of men given a combination regimen in which copper tripeptide was one of many ingredients of one component.	Uncontrolled; approved drugs in the same regimen; the copper peptide contribution cannot be separated.	Evidence grade B
Lee 2016 Ann Dermatol Hair research	Humantopical Men with pattern hair loss Derivative or conjugate · n = 45	The study measured hair count, length and thickness at 1, 3 and 6 months; hair-count change differed from placebo in the lower-strength group, while length and thickness did not differ between groups.	Copper-free GHK complexed with 5-ALA, so it is not a GHK-Cu study; small groups; single centre.	Evidence grade B

Frequently asked questions

Is there a GHK-Cu hair trial?

No randomised trial of GHK-Cu on its own for hair is indexed in PubMed. The one placebo-controlled study used a complex of copper-free GHK with 5-aminolevulinic acid; the others tested multi-ingredient products without control groups.

What does the 2026 systematic review on peptides for hair say about GHK?

It included 14 human studies of peptide-containing formulations and graded them by formulation. GHK appears only as one component of combinations, so the grades do not apply to GHK or GHK-Cu alone.

References

Lee WJ, Sim HB, Jang YH et al. (2016). Efficacy of a Complex of 5-Aminolevulinic Acid and Glycyl-Histidyl-Lysine Peptide on Hair Growth. Ann Dermatol. PubMed 27489425 · doi:10.5021/ad.2016.28.4.438[Human, grade B]
Kapoor R, Shome D (2018). Intradermal injections of a hair growth factor formulation for enhancement of human hair regrowth - safety and efficacy evaluation in a first-in-man pilot clinical study. J Cosmet Laser Ther. PubMed 29482481 · doi:10.1080/14764172.2018.1439965[Human, grade B]
Tanaka Y, Aso T, Ono J et al. (2018). Androgenetic Alopecia Treatment in Asian Men. J Clin Aesthet Dermatol. PubMed 30057663[Human, grade B]
Patel MN, Patel N, Merja A et al. (2024). An Assessment of the Safety, Efficacy, and Tolerability of a Novel Scalp Treatment Regimen Combining a Hydroxy Acid-Based Scrub and Copper Tripeptide Serum in the Management of Seborrheic Dermatitis in Adults. Cureus. PubMed 39449909 · doi:10.7759/cureus.70108[Human, grade B]
Kapoor R, Shome D, Vadera S et al. (2020). QR678 & QR678 Neo Hair Growth Formulations: A Cellular Toxicity & Animal Efficacy Study. Plast Reconstr Surg Glob Open. PubMed 32983753 · doi:10.1097/GOX.0000000000002843[Animal, grade C]
Joerg L, Zafar K, Jagdeo J (2026). Peptides for Hair Growth and Treatment of Hair Loss and Alopecia: A Systematic Review. J Drugs Dermatol. PubMed 42976838 · doi:10.36849/JDD.9736[Review, grade R]