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FGL
Neuroprotective & Cognitive EnhancersFGL (FG loop peptide) is a synthetic neuropeptide derived from NCAM sequences that promotes neural repair, neurotrophin signaling, and memory formation. It enhances learning via FGFR1 activation and is under investigation for cognitive impairment, Alzheimer’s, and ischemia recovery. Delivered intranasally, it bypasses the BBB and targets brain-specific pathways.
Reconstitute
2 mL BAC + 10mg vial
50 mcg/unit
Daily Range
200–800 mcg Intranasal
3–5x per week
Standard Dose
400 mcg
Cycle
4–8 weeks
then reassess
FGLFG loop peptideneural cell adhesion moleculememoryneuroplasticity
Dosing & Reconstitution Guide
In rodents, FGL is administered intranasally or via injection at doses of 0.1–1.0 mg/kg. These studies are exploratory and not approved for clinical use.
Standard / Gradual Approach
10mg VialstandardPhaseDoseVolume
Weeks 1–2200 mcg intranasal 3x/week4 units per dose
Weeks 3–6400 mcg intranasal 3–5x/week8 units per dose
Weeks 7–12400–800 mcg 3–5x/week8–16 units per dose
Protocol Summary
Intranasal: 3–5x per week · Dose range 200–800 mcg with gradual titration
Cycle Length: 4–8 weeks typical; reassess before extending
Frequency & Cycling
Intranasal
Recommended protocol: 3–5x weekly for 6–12 weeks. Repeat every 3–6 months based on cognitive goals.
🧪 Quick Start
Vial Size
10 mg
BAC Water
2 mL
Concentration
5000 mcg/unit
Potential Benefits & Use Cases
FGL is an experimental peptide used in preclinical research. Not approved for human use.
Stimulates neurite outgrowth and synaptic regeneration
Studied for antidepressant-like activity in animal models
May improve memory consolidation and retention
Binds NCAM receptors and activates Fyn kinase pathways
Investigated for potential in neurodegenerative disorders
Clinical data Strong preclinical Limited data
Mechanism of Action
→Binds neural cell adhesion molecules (NCAMs)
→Activates FGFR1 signaling, enhancing LTP and memory
→Increases neurotrophin availability including BDNF and NGF
→Reduces apoptosis in neurons post-injury or stress
Stacking Synergies
+
Elamipretide
Enhances LTP and memory acquisition in tandem with nootropic compounds
+
Semax
Synergistic with Semax for neurotrophic and neurovascular optimization
+
PACAP
Complementary neurovascular support and CNS receptor activation with PACAP
Lifestyle & Optimization
diet
Adequate omega-3 intake (EPA/DHA).
sleep
Quality sleep. Reduce chronic stress which impairs neuroplasticity.
timing
Consistent dosing schedule.
exercise
Regular aerobic exercise. Pair with cognitive challenges (learning a language, puzzles) to leverage NCAM-mediated synaptic enhancement.
Peptide Research & Preclinical Studies
Evidence-Based Research Findings
Side Effects & Safety
Common Side Effects
• Mild nasal irritation
• Transient fatigue
Contraindications & Warnings
• Should be used under supervision in patients with neuropsychiatric disorders
• Avoid high doses without guidance due to excitatory synaptic effects
Long-Term Safety Data
• No long-term toxicity reported in animal studies; human data is limited
🧮 Dose Calculator
Concentration
50.0
mcg/unit
Draw Volume
10
units (0.100 mL)
For a 500 mcg dose, draw 10 units on a U-100 insulin syringe
🧬
Bioavailability & Absorption
SubQ Injection
Not commonly used; limited CNS targeting via this route
Oral Administration
Poor due to enzymatic degradation and first-pass metabolism
Intranasal
High brain bioavailability through nasal delivery targeting olfactory bulb
Half-Life
Estimated 30–60 minutes
Degradation
Cleared enzymatically in brain and blood plasma
Tissue Specificity
Hippocampus, prefrontal cortex, and CNS synaptic sites
⚗️
Peptide Details
Molecular Weight
1226.6
Formula
C57H98N18O12S
Sequence
EVYVVAENQQGKSKA
⚖️
Legal Status & Regulatory
RegionStatus
EUNot Approved
FDANot Approved
CanadaNot Approved
AustraliaNot Approved
Storage Instructions
Lyophilized (Powder)
Store at -20°C or 2–8°C. Protect from light and moisture.
Reconstituted (Mixed)
Refrigerate at 2–8°C. Use within 3–4 weeks. Transfer to nasal spray bottle for intranasal use.