GHK-Cu: what the research says.

GHK-Cu is a tripeptide complex consisting of three amino acids (glycine, histidine, lysine) bound to a copper(II) ion. The tripeptide sequence Gly-His-Lys has high natural affinity for copper, and the peptide-copper complex is the biologically active form. It is sometimes referred to as copper tripeptide-1, copper peptide GHK, or by the historical research name Lamin.

The molecule was first isolated and characterized by Loren Pickart, then a graduate student at the University of California, San Francisco. Pickart’s 1973 PhD work, later published in the Journal of Cellular Physiology (1973) and Nature (1980, with Thaler), described a plasma factor that restored aged liver tissue function in albumin-gradient experiments. The active factor was identified as the GHK tripeptide, naturally complexed with copper in circulation.

Plasma GHK levels in humans decline substantially with age, falling roughly from 200 ng/mL in the third decade to under 80 ng/mL by the seventh decade. That observation, reported by Pickart and colleagues across multiple publications, framed GHK-Cu as both a wound-response signal and a candidate marker of regenerative capacity, and shaped the research program that followed.

GHK-Cu shows up in three distinct delivery contexts, and conflating them is the most common analytical error in popular writing on the molecule:

• Topical cosmetic creams and serums. Widely sold over-the-counter as cosmetic ingredients. This is the best-studied delivery route in human subjects (Leyden et al., 2002; Finkley et al., 2005) and has decades of consumer use. Cosmetic-grade copper-peptide formulations are not regulated as drugs.
• Wound-care dressings. Hydrogel and matrix-style dressings incorporating copper peptides have been studied in chronic-wound and post-surgical contexts. Dressing-based delivery is topical and localized.
• Compounded injectable.A parenteral GHK-Cu solution formulated for subcutaneous or intramuscular use. This is the form referenced by the FDA’s April 15, 2026 list of Category-unclassified peptides. Systemic injection of GHK-Cu is not equivalent to topical application: dose distribution, copper exposure, and clinical evidence base all differ.

Some practitioners also discuss intranasal delivery (for putative central effects) and microneedling-assisted topical delivery (to cross the stratum corneum). Both sit outside the well-controlled clinical literature.

This is research context, not prescribing guidance. PepScribe does not currently offer injectable GHK-Cu, and this material should not be interpreted as a dosing or formulation recommendation.

GHK-Cu’s regulatory status splits cleanly along route of administration, and the distinction is the most important fact about the molecule for a US consumer:

Topical cosmetic GHK-Cu is widely sold over-the-counter as a cosmetic ingredient. It is not approved by FDA as a drug, but cosmetic regulation is a separate framework, and GHK-Cu has been a staple of cosmetic-grade copper-peptide formulations for years.

Injectable GHK-Cuis the transitional surface. It is not an FDA-approved drug. The FDA April 15, 2026 bulk-substance list flagged injectable GHK-Cu among the peptides removed from Category 2 but not yet placed on Category 1, pending Pharmacy Compounding Advisory Committee review. Some 503A compounding pharmacies are preparing it under the interpretation that “removal lifts prohibition,” but the regulatory status remains unsettled until PCAC review concludes (most listed peptides July 23–24, 2026; remainder by end of February 2027).

Practical implication: a consumer can buy a topical copper-peptide cream without medical involvement; a compounded injectable form requires a clinician evaluation and a prescription, sits in unsettled regulatory territory, and should be approached with that ambiguity in mind. Gray-market injectable products labeled as GHK-Cu, sold outside licensed compounding channels, are unregulated research chemicals without pharmaceutical-grade quality assurance.