Human Growth Hormone (HGH) vs FGL
A detailed comparison to help you understand the differences and choose the right peptide for your research goals.
Human Growth Hormone (HGH)
Human Growth Hormone (somatropin) is a 191-amino acid protein identical to naturally produced GH. FDA-approved for growth hormone deficiency, Turner syndrome, and other conditions. Widely used off-label for anti-aging and performance.
Full details →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 →Side-by-Side Comparison
| Aspect | Human Growth Hormone (HGH) | FGL |
|---|---|---|
| Mechanism | Binds to GH receptors throughout the body, stimulating IGF-1 production in the liver. Promotes protein synthesis, fat metabolism, and cellular regeneration across multiple tissues. | Binds to FGFR1 (fibroblast growth factor receptor 1) to activate downstream signaling cascades that promote neurite outgrowth, synaptic plasticity, and neuronal survival. |
| Typical Dosage | Medical: 0.1-0.3mg/kg/week divided into daily doses. Anti-aging: 1-2 IU daily. Performance: 2-6 IU daily, sometimes higher. | Research protocols have used subcutaneous doses ranging from 1-10mg. Intranasal administration also studied. Optimal dosing not established. |
| Administration | Subcutaneous injection, preferably at night to mimic natural pulsatile release. Rotate injection sites. Store refrigerated. | Subcutaneous injection or intranasal administration. Research compound with limited human dosing data. |
| Side Effects | Joint pain, water retention, carpal tunnel syndrome, potential insulin resistance, and acromegaly features with long-term high doses. | Limited human data available. Animal studies show good tolerability. |
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