FGL vs Noopept
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.
Full details →Noopept
Noopept (N-phenylacetyl-L-prolylglycine ethyl ester) is a peptide-derived nootropic developed in Russia. While technically a dipeptide prodrug rather than a true peptide, it's often discussed alongside peptide nootropics.
Full details →Side-by-Side Comparison
| Aspect | FGL | Noopept |
|---|---|---|
| Mechanism | Binds to FGFR1 (fibroblast growth factor receptor 1) to activate downstream signaling cascades that promote neurite outgrowth, synaptic plasticity, and neuronal survival. | Metabolized to cycloprolylglycine which modulates AMPA and NMDA receptors, increases NGF and BDNF expression, and provides neuroprotective effects through antioxidant mechanisms. |
| Typical Dosage | Research protocols have used subcutaneous doses ranging from 1-10mg. Intranasal administration also studied. Optimal dosing not established. | Oral: 10-30mg daily, typically divided into 2-3 doses. Sublingual use may enhance absorption. Some users go higher but effects may plateau. |
| Administration | Subcutaneous injection or intranasal administration. Research compound with limited human dosing data. | Oral or sublingual administration. Unlike most peptides, it's orally bioavailable. Can be taken with or without food. |
| Side Effects | Limited human data available. Animal studies show good tolerability. | Headache (often from choline depletion), irritability, insomnia if taken late, and occasional brain fog during initial use. |
| Best For |
What They Have in Common
Both FGL and Noopept are commonly used for: