Skin & Hair.

GHK-Cu (Glycyl-L-histidyl-L-lysine copper complex) is a naturally occurring tripeptide-copper complex that declines with age — plasma levels fall approximately 60% between ages 20 and 60. Its primary mechanism is regulation of MMP/TIMP balance in the extracellular matrix: it downregulates matrix metalloproteinases responsible for collagen degradation while upregulating tissue inhibitors of metalloproteinases, shifting the net balance from breakdown toward synthesis and remodelling. This drives measurable increases in collagen Type I and III and elastin production. Beyond the extracellular matrix, GHK-Cu modulates approximately 2,000 RNA expression signatures — a genomic footprint documented in peer-reviewed literature and validated in controlled clinical trials on ageing skin. Hair follicle activation is a well-documented secondary effect, making it relevant for scalp and hair density goals alongside skin anti-ageing. Effective both topically and subcutaneously.

Best for · The primary compound for anti-ageing, wrinkle reduction, skin firmness, collagen synthesis, and hair follicle support. The strongest scientific anchor in this stack and the recommended starting point for any skin-focused protocol.

BPC-157 (Body Protection Compound-157) is a synthetic pentadecapeptide derived from a protein found in gastric juice. In the skin context, its key mechanisms are angiogenesis (new blood vessel formation to supply repair sites), collagen deposition, and local anti-inflammatory signalling that reduces scar tissue formation. It upregulates nitric oxide synthesis and growth factor expression at wound sites, accelerating both epithelial and dermal healing. The framing here is post-procedure and scar-specific — different from its tendon and ligament angle in the Recovery stack. For skin, BPC-157 is particularly relevant following microneedling, laser resurfacing, chemical peels, or surgical procedures where accelerated wound closure and minimised scarring are the priority.

Best for · Post-procedure recovery (laser, microneedling, surgery), active scarring patterns, or users who want to layer systemic wound-healing depth on top of the GHK-Cu collagen foundation.

TB-500 (Thymosin Beta-4 synthetic analogue) is a peptide that promotes systemic tissue mobilisation by upregulating actin polymerisation and cell migration. In dermal and hair contexts, its primary relevance is angiogenic: it promotes new capillary formation to repair sites and facilitates migration of stem cells and progenitor cells to areas of damage. This systemic tissue-regeneration signal extends the stack's reach beyond the local BPC-157 effect — supporting hair follicle regrowth and dermal repair in areas that require new vascularisation rather than just local wound healing.

Best for · Users wanting the complete regenerative depth — particularly those with hair regrowth goals or post-procedure cases where systemic angiogenic support meaningfully extends recovery beyond what GHK-Cu and BPC-157 alone produce.

Pre-mixed TB-500 and BPC-157 in a single vial, combining the systemic angiogenic and stem-cell mobilisation signal of TB-500 with the local wound-healing, collagen-deposition, and scar-minimisation effects of BPC-157. In skin contexts, this combination addresses both the systemic depth (new blood vessel formation, progenitor cell migration) and the local repair layer (collagen deposition, reduced scarring) in a single injection. The convenience formulation for users running both compounds — clinically equivalent to separate vials but reduces injection burden.

Best for · Pro-tier users who want both BPC-157 and TB-500 with minimal preparation, particularly post-procedure or hair regrowth protocols where both wound-healing and angiogenic depth are needed simultaneously.

Melanotan-2 is a synthetic analogue of alpha-melanocyte-stimulating hormone (α-MSH) that acts as an agonist at MC1R and MC4R receptors. MC1R activation drives eumelanin synthesis in melanocytes — producing skin pigmentation (tanning) that functions as a photoprotective response against UV radiation. The resulting melanin absorbs and dissipates UV energy, offering genuine (not cosmetic) UV protection via the same mechanism the body uses naturally, but at an amplified magnitude. MC4R agonism also produces libido-enhancing effects, which some users seek independently. Its mechanism is entirely distinct from the collagen and repair axis of the other compounds in this stack — Melanotan-2 does not stimulate collagen synthesis, does not modulate MMP/TIMP, and does not contribute to wound healing. Adverse effects include transient nausea (especially at higher doses), facial flushing, hyperpigmentation in pre-existing naevi, potential activation of atypical moles, and modest blood pressure increases. These are real and require informed patient selection.

Best for · Users whose primary goal is UV photoprotection or melanin-based pigmentation — a distinct goal axis from collagen anti-ageing. Not a tier-up from GHK-Cu; a fork into a different objective. Requires careful patient screening for melanoma history and existing atypical naevi.