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Cosmetic & Skin

GHK (copper-free)

Also known as Glycyl-L-Histidyl-L-Lysine · GHK tripeptide · Tripeptide-1

PreliminaryTopicalNot an FDA-approved drug for any indication. In topical/cosmetic products it is handled as a cosmetic ingredient (commonly labeled under the INCI name Tripeptide-1), which the FDA does not pre-approve. The related copper complex GHK-Cu has been the subject of FDA compounding-list activity: injectable GHK-Cu was among peptides removed from the FDA interim 503A Category 2 list effective April 22, 2026, but removal from Category 2 does not place a substance on the 503A bulks list, so it remains unlawful to compound unless and until formally added, pending separate Pharmacy Compounding Advisory Committee review. Copper-free GHK itself has no FDA drug approval. GHK is not currently named on the WADA Prohibited List, but athletes should verify current WADA status before use.

GHK (glycyl-L-histidyl-L-lysine) is a small tripeptide found naturally in human plasma, saliva, and urine, first isolated by Pickart in 1973; its plasma level declines with age. The "copper-free" form refers to the apo-peptide that is not pre-complexed with copper, in contrast to the more extensively studied copper complex GHK-Cu. In laboratory and animal models, GHK has been associated with modulation of collagen, glycosaminoglycan, and proteoglycan turnover, regulation of matrix metalloproteinases, and broad gene-expression and antioxidant effects, though much of this activity is attributed to copper binding. Notably, evidence on the copper-free form alone is mixed and debated: at least one animal wound study found copper-free GHK had no collagen-stimulating effect while only GHK-Cu did, whereas some other reports describe activity without copper. Overall the rigorous, controlled data centers on GHK-Cu, leaving the independent efficacy of the copper-free form largely preclinical and unsettled.

Studied / used for

  • Investigated for collagen, glycosaminoglycan, and proteoglycan turnover in skin models
  • Studied for modulation of matrix metalloproteinases and their inhibitors
  • Investigated for skin regeneration and wound-healing-related gene expression
  • Studied for antioxidant and anti-inflammatory signaling in preclinical models
  • Investigated as a topical anti-aging cosmetic peptide

Commonly reported side effects

  • Mild skin irritation commonly reported with topical use
  • Redness or transient stinging at the application site
  • Skin sensitivity or contact sensitivity reactions reported by some users
  • Itching reported with topical use
Preliminary. Mostly early or animal studies. This reflects the strength of the research base, not effectiveness or a recommendation.

Not medical advice.

This is an educational reference. Peptalk does not recommend, prescribe, endorse, or rate any compound, and provides no dosing information. Do not start, stop, or change any peptide, hormone, supplement, or therapy based on this page. All clinical decisions must be made with your licensed healthcare provider.

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