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ToolsCompareHexarelin vs Syn-Coll

Hexarelin vs Syn-Coll

Side-by-side comparison of key properties, dosing, and research.

Growth Hormone Peptides
Hexarelin
Skin & CosmeticAnti-Aging & Longevity
Syn-Coll
Summary
Hexarelin is a potent synthetic GHRP and the strongest GH secretagogue in its class per unit dose. It also exhibits unique cardioprotective properties through direct binding to cardiac CD36 receptors, independent of GH release. Its potency is balanced by a tendency to desensitize GH release with prolonged use, making cycling important.
Syn-Coll is a palmitoylated tripeptide (Palmitoyl Tripeptide-5) that mimics thrombospondin-1 to activate TGF-beta, the primary growth factor driving collagen synthesis in the dermis. It is one of the most mechanistically direct collagen-stimulating peptides in cosmetic formulations.
Half-Life
~70 minutes
Extended (lipid depot in stratum corneum)
Admin Route
SubQ
Topical
Research
Typical Dose
100–200 mcg
0.005-0.05% in formulation
Frequency
2–3 times daily
Once or twice daily
Key Benefits
  • Strongest GH pulse per mcg among GHRPs
  • Unique direct cardioprotective effects via CD36
  • Increased IGF-1 and muscle anabolism
  • Accelerated recovery from training
  • Bone density support
  • Anti-aging via GH axis
  • Potential cardiac rehabilitation benefits
  • Directly activates TGF-beta for potent collagen synthesis stimulation
  • Increases dermal thickness and firmness
  • Reduces depth of wrinkles and fine lines
  • Improves skin elasticity
  • Clinically validated in collagen induction studies
  • Complementary to retinoids or vitamin C
Side Effects
  • Water retention
  • Elevated cortisol
  • Elevated prolactin (more pronounced than other GHRPs)
  • Receptor desensitization with continuous use
  • +1 more
  • Generally well-tolerated
  • Rare mild irritation at high concentrations
  • Possible sensitivity in individuals with inflammatory skin conditions
Stacks With