Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.
| GHK (without copper) | LL-37 (Cathelicidin) | |
|---|---|---|
| Category | Peptides | Peptides |
| Standard Dose | Research indicates 1-3% concentration in topical formulations. Injectable dosing follows GHK-Cu protocols at 1-2 mg daily. | Research indicates 50-100 mcg daily via subcutaneous injection for immune support. |
| Timing | Topical application morning and evening. Injectable in evening. | Morning administration preferred for immune support. Topical application directly to wound sites. |
| Cycle Duration | Topical use can be ongoing indefinitely. Injectable cycles 8-12 weeks. | 4-8 week cycles. Short-term use preferred due to limited long-term safety data. |
| Evidence Level | moderate_human | animal_plus_anecdotal |
GHK (glycyl-L-histidyl-L-lysine) is a naturally occurring tripeptide found in human plasma, saliva, and urine that has an extremely high affinity for copper(II) ions. Even without exogenously complexed copper, GHK rapidly chelates available copper in biological systems, making copper-free GHK functionally similar to GHK-Cu in vivo. The peptide stimulates collagen and glycosaminoglycan synthesis, modulates metalloproteinase activity, resets gene expression patterns toward a healthier state (affecting 31.2% of human genes), and activates wound healing cascades.
Research indicates 1-3% concentration in topical formulations. Injectable dosing follows GHK-Cu protocols at 1-2 mg daily.
Topical application morning and evening. Injectable in evening.
Topical use can be ongoing indefinitely. Injectable cycles 8-12 weeks.
LL-37 is a 37-residue amphipathic helical antimicrobial peptide, the only human cathelicidin, that kills bacteria by forming tetrameric channels that perforate cytoplasmic membranes. Beyond direct antimicrobial activity, it modulates innate immunity through formyl-peptide receptor 2 (FPR2), induces chemotaxis of neutrophils and monocytes, upregulates CXCR4 and IL-8, and neutralizes bacterial endotoxins (LPS). It also promotes wound healing through keratinocyte migration and angiogenesis.
Research indicates 50-100 mcg daily via subcutaneous injection for immune support.
Morning administration preferred for immune support. Topical application directly to wound sites.
4-8 week cycles. Short-term use preferred due to limited long-term safety data.
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