FGL vs AHK-Cu

A detailed comparison to help you understand the differences and choose the right peptide for your research goals.

FGL

FGL (FG Loop) is a synthetic peptide that mimics the neural cell adhesion molecule (NCAM) FG loop region. It promotes neuroplasticity and has shown cognitive-enhancing effects in research.

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AHK-Cu

AHK-Cu (Copper Tripeptide-3, Alanine-Histidine-Lysine Copper) is a copper peptide similar to GHK-Cu but with different properties. It's used for hair growth and skin rejuvenation applications.

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Side-by-Side Comparison

AspectFGLAHK-Cu
MechanismBinds to FGFR1 (fibroblast growth factor receptor 1) to activate downstream signaling cascades that promote neurite outgrowth, synaptic plasticity, and neuronal survival.The copper-binding tripeptide stimulates collagen synthesis and may promote hair follicle enlargement. Works similarly to GHK-Cu but may have distinct receptor interactions.
Typical DosageResearch protocols have used subcutaneous doses ranging from 1-10mg. Intranasal administration also studied. Optimal dosing not established.Topical: 0.5-2% concentration in serums for skin or scalp applications. Often combined with other growth factors for hair formulations.
AdministrationSubcutaneous injection or intranasal administration. Research compound with limited human dosing data.Topical application to skin or scalp. Can be used with microneedling for enhanced penetration. May cause temporary blue-green tint at high concentrations.
Side EffectsLimited human data available. Animal studies show good tolerability.Generally well-tolerated. May cause skin irritation in sensitive individuals. Temporary discoloration possible.
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Key Differences

Unique to FGL:

Unique to AHK-Cu:

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