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ToolsCompareKisspeptin-10 vs P21

Kisspeptin-10 vs P21

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

Sexual Health & LibidoAnti-Aging & Longevity
Kisspeptin-10
Cognitive EnhancementAnti-Aging & Longevity
P21
Summary
Kisspeptin-10 is the biologically active C-terminal decapeptide of kisspeptin, an endogenous regulator of the reproductive axis. It acts upstream of GnRH to potently stimulate LH and testosterone release, and plays a key role in sexual arousal and libido.
P21 is a synthetic peptide derived from CNTF (ciliary neurotrophic factor) that promotes hippocampal neurogenesis, enhances memory and spatial learning, and may reduce amyloid-beta pathology. It is used as a neurogenic and cognitive enhancer with potential anti-Alzheimer's applications.
Half-Life
~4 minutes (rapidly degraded); longer-acting analogs like TAK-448 are in development
Not well characterized; likely short, but neurogenic effects persist long after administration
Admin Route
SubQ, IV
SubQ, Intranasal
Research
Typical Dose
50–500 mcg
100–500 mcg
Frequency
Once daily to every other day
Once daily
Key Benefits
  • Potently stimulates LH and testosterone
  • Enhances sexual arousal and libido
  • Activates HPG axis — upstream of GnRH
  • May improve fertility in hypogonadotropic hypogonadism
  • Increases brain activation in sexual attraction circuits
  • May restore LH pulsatility in suppressed HPG axis
  • Promotes hippocampal neurogenesis
  • Enhances spatial memory and learning
  • Increases BDNF expression
  • Reduces amyloid-beta plaque formation (animal models)
  • Anti-tau pathology potential
  • Cognitive enhancement without stimulant effects
  • Potential therapeutic for Alzheimer's and cognitive aging
Side Effects
  • Injection site reactions
  • Temporary nausea
  • Flushing
  • Elevated LH/testosterone (intended effect)
  • +1 more
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
Stacks With