ResearchSafe

FGL (FGL (NCAM-Derived Peptide))

Category: Cognitive & Nootropic. Status: Research compound.

A peptide from the FG loop of neural cell adhesion molecule (NCAM). Enhances synaptic plasticity, memory, and neurotrophic effects through FGFR activation.

How it works

Mimics NCAM FG loop interacting with FGFR1 to promote LTP, neurite outgrowth, neuronal survival, and presynaptic function enhancement.

Key facts

  • Molecular weight: ~1,800 Da
  • Half-life: 4-8 hours
  • Bioavailability: Moderate (SubQ, partial BBB crossing)
  • Storage: Lyophilized: -20°C.

Dosing overview

  • Typical dose: 1-5 mg/kg (research)
  • Frequency: Daily or every other day
  • Duration: 2-4 weeks
  • Route: Subcutaneous

Reported benefits

  • Synaptic plasticity
  • LTP facilitation
  • Memory improvement
  • Neurotrophic effects
  • FGFR activation

Possible side effects

  • Limited data
  • Theoretical mitogenic concern
  • Injection site reaction

Research

  • FGL enhances hippocampal LTP and memory in aged rats (2020): Restored LTP to young-adult levels and improved contextual fear memory by 45%.
  • NCAM-derived peptides for cognitive enhancement (2019): Improved social memory and reduced anxiety through FGFR1-dependent synaptic modulation.

Community reviews of FGL

Rated 4.4 out of 5 from 7 community reviews by ResearchSafe members.

  • baseline_ben rated it 4/5 - Genuinely effective after 1 month: Been using FGL for about 1 month and the results are clear. Not overnight dramatic, but a steady, consistent improvement that became undeniable by the end of the first month. The mechanism makes sense based on what I have read in the literature, and my subjective experience matches the expected timeline. Benefits built gradually and plateaued at a good level. Side effects were minimal to none at the dose I used. Followed proper protocols for sourcing, storage, and administration. Would recommend to others who have done their research and have realistic expectations.
  • halflife_harry rated it 5/5 - Solid compound with real results: Been using FGL for about 3 months and the results are clear. Not overnight dramatic, but a steady, consistent improvement that became undeniable by the end of the first month. The mechanism makes sense based on what I have read in the literature, and my subjective experience matches the expected timeline. Benefits built gradually and plateaued at a good level. Side effects were minimal to none at the dose I used. Followed proper protocols for sourcing, storage, and administration. Would recommend to others who have done their research and have realistic expectations.
  • measured_mike rated it 5/5 - Noticed clear benefits within weeks: Added FGL to my protocol about 2 months ago and it has earned its place. The benefits became noticeable around week 2-3 and have been consistent since. What I appreciate about this compound is the predictability. It does what the research suggests it should do, at roughly the timeline you would expect. No surprises, no dramatic swings, just steady improvement. No notable side effects to report at my dose. Sourcing is always the challenge with research compounds, insist on third-party testing. Storage and reconstitution per standard protocols. Plan to continue.
  • lab_notes_tom rated it 5/5 - Worth adding to the protocol: FGL has been a worthwhile addition. I am data-driven and tracked relevant markers before, during, and after. The improvement is measurable and correlates with the intervention timeline. What sets this apart from some compounds I have tried is the consistency. Benefits did not fluctuate wildly or disappear. They built up and maintained. That gives me confidence in the mechanism. Tolerance has been excellent. Nothing in my bloodwork or subjective experience raised any flags. This is the kind of compound that does its job quietly without causing problems. Exactly what you want.
  • nightryan rated it 4/5 - FGL gave me a cleaner mental edge at work: I ran FGL for about 3 weeks because my days are a weird mix of PT charting, patient juggling, and trying to keep my own head sharp after a long commute on the East Coast. For me, it seemed to make recall and verbal flow a little smoother, like the words came up faster when I was explaining exercises or sorting out notes. I didn’t get some crazy buzzy nootropic feel, just a subtle cleaner focus. Only caveat, the effect was mild enough that if I skipped a dose I wasn’t chasing it hard.
  • restless_peptidehead rated it 4/5 - Quiet focus for teaching days, with one small catch: I tried FGL for about four months while juggling yoga teaching, lesson planning, and the usual brain fog that comes with being in my mid-40s and trying to stay sharp without living on caffeine. For me it seemed to make reading, writing class notes, and switching between tasks feel a bit smoother, especially on busy mornings when I had back-to-back sessions. I noticed it most when I was preparing sequences and cues, which is exactly the sort of work I need my head to cooperate with. The only thing I found a bit annoying was that the effect felt subtle, so I had to pay attention to notice it.

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Community discussions about FGL

Research and educational reference only. Not medical advice.