GHK-Cu (Copper Peptide) vs P21
A detailed comparison to help you understand the differences and choose the right peptide for your research goals.
GHK-Cu (Copper Peptide)
GHK-Cu is a naturally occurring copper peptide found in human plasma, saliva, and urine. It plays important roles in wound healing, tissue repair, and has shown anti-aging properties in research.
Full details →P21
P21 is a synthetic peptide derived from Cerebrolysin, specifically designed to mimic the neurotrophic effects of the parent compound. It promotes neurogenesis and has shown cognitive-enhancing properties in research.
Full details →Side-by-Side Comparison
| Aspect | GHK-Cu (Copper Peptide) | P21 |
|---|---|---|
| Mechanism | Attracts immune cells and fibroblasts to wound sites, stimulates collagen and glycosaminoglycan synthesis, promotes angiogenesis, and has antioxidant effects. Modulates gene expression related to tissue repair. | Inhibits glycogen synthase kinase-3β (GSK-3β) and activates CREB signaling pathway. This promotes BDNF expression, neurogenesis in the hippocampus, and synaptic plasticity. |
| Typical Dosage | Topical: Applied as serum or cream 1-2 times daily. Injectable: 1-2mg daily for research purposes. Microneedling protocols often use 0.5-1%. | Research protocols typically use 1-5mg administered intranasally or subcutaneously. Often used in cycles of 2-4 weeks. |
| Administration | Most commonly used topically for skin applications. Can be injected subcutaneously for systemic effects. Often combined with microneedling for enhanced skin penetration. | Can be administered intranasally for direct CNS access or subcutaneously. Best used cyclically rather than continuously. |
| Side Effects | Topical use is generally well-tolerated. May cause temporary skin irritation or redness in sensitive individuals. Injectable use may cause injection site reactions. | Limited data. Reported effects include mild headache, temporary brain fog during initial use, and fatigue. |
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