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ToolsCompareAHK-Cu vs HGH Fragment 176-191

AHK-Cu vs HGH Fragment 176-191

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

Skin & CosmeticAnti-Aging & Longevity
AHK-Cu
Fat Loss & Metabolic
HGH Fragment 176-191
Summary
AHK-Cu is a copper tripeptide composed of alanine, histidine, and lysine chelated to copper. Distinct from GHK-Cu, AHK-Cu exhibits strong affinity for hair follicle receptors and demonstrates potent hair growth stimulation alongside wound healing and skin regeneration properties.
HGH Fragment 176-191 (also known as AOD-9604) is a stabilized, modified fragment of the human growth hormone molecule corresponding to amino acids 176–191 with an addition of a tyrosine residue at the N-terminus. It retains HGH's fat-burning properties without the anabolic, diabetogenic, or IGF-1-stimulating effects.
Half-Life
Hours (topical, variable by formulation)
~30 minutes
Admin Route
Topical, Scalp application, Subcutaneous (research)
SubQ
Research
Typical Dose
0.01–0.1% concentration
250–500 mcg
Frequency
Once or twice daily
1–3 times daily
Key Benefits
  • Stimulates hair follicle growth and reduces shedding
  • Increases dermal papilla cell proliferation
  • Promotes wound healing and skin regeneration
  • Antioxidant protection via superoxide dismutase activation
  • Improves skin elasticity and firmness
  • Supports collagen and elastin production
  • Selective fat burning without anabolic side effects
  • Reduces visceral and subcutaneous fat
  • No insulin resistance or blood glucose disruption
  • Does not stimulate IGF-1
  • May support cartilage and bone repair (at higher doses)
  • No effect on growth or organ size
Side Effects
  • Generally well-tolerated topically
  • Mild scalp irritation or redness in sensitive individuals
  • Possible temporary hair shedding phase at treatment initiation
  • Copper accumulation with excessive systemic use (rare)
  • Injection site irritation
  • Temporary lethargy
  • Headache (rare)
  • Nausea (rare)
Stacks With