AHK-Cu

AHK-Cu is a copper-binding tripeptide (Ala-His-Lys) structurally related to GHK-Cu but with distinct biological activity favoring hair follicle stimulation. It has shown the ability to stimulate hair growth and increase hair follicle size in preclinical studies, positioning it as a topical peptide for hair loss treatment. It is used in cosmeceutical and trichology formulations alongside GHK-Cu.

AHK-Cu delivers copper ions to hair follicles and skin, stimulating dermal papilla cell proliferation and increasing hair follicle size. It upregulates VEGF (vascularization of hair follicle), promotes Wnt/beta-catenin signaling (hair follicle stem cell activation), and enhances extracellular matrix protein production. The tripeptide backbone provides targeted copper delivery, and AHK-Cu appears to have stronger hair growth-specific effects than GHK-Cu based on in vitro hair follicle organ culture studies.

No FDA-approved indications (cosmetic use). Research/cosmeceutical: androgenetic alopecia (topical), hair thinning, scalp health, wound healing (topical), skin rejuvenation.

In vitro studies demonstrate AHK-Cu stimulates human hair follicle growth in organ culture and increases dermal papilla cell proliferation. Limited published data compared to GHK-Cu. A few small clinical observations in trichology clinics suggest improved hair density with topical or mesotherapy application. No RCTs. Evidence base is early-stage and largely preclinical. Often used empirically in combination with GHK-Cu, minoxidil, and microneedling.

Topical: generally well-tolerated. Rare skin irritation or contact sensitivity. Copper peptides in general have a good topical safety profile. Mesotherapy: injection site reactions, bruising, infection risk (standard injection risks). Systemic copper toxicity not a concern at topical cosmeceutical concentrations.

Unclassified — cosmeceutical ingredient. Not regulated as a drug. Available in topical formulations from compounding pharmacies and cosmeceutical companies. No FDA oversight for cosmetic use.

Drug Interactions: May be combined with minoxidil, finasteride, and other hair loss treatments. No known systemic interactions for topical use. Monitoring: Clinical hair assessments, trichoscopy, photography. Research Gaps: No RCTs. Head-to-head with GHK-Cu for hair growth. Optimal concentration, formulation, and application frequency. Systemic safety of mesotherapy delivery.