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ToolsComparePE-22-28 vs PT-141 (Bremelanotide)

PE-22-28 vs PT-141 (Bremelanotide)

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

Cognitive Enhancement
PE-22-28
Sexual Health & Libido
PT-141 (Bremelanotide)
Summary
PE-22-28 is a synthetic analog of spadin derived from sortilin, designed to block TREK-1 potassium channels with rapid-onset antidepressant and neurogenic effects. It shows fast-acting depression relief (within 24 hours) and promotes hippocampal neurogenesis.
PT-141 (Bremelanotide) is a cyclic peptide melanocortin receptor agonist that enhances sexual desire and arousal through central nervous system mechanisms. It is FDA-approved as Vyleesi for premenopausal women with hypoactive sexual desire disorder (HSDD).
Half-Life
Relatively short; CNS effects may persist due to neurogenic mechanisms
2–3 hours
Admin Route
SubQ, Intranasal
SubQ
Research
Typical Dose
200–400 mcg
0.5–1.75 mg
Frequency
Once daily
As needed (not daily)
Key Benefits
  • Rapid-onset antidepressant effects (within 24 hours)
  • Promotes hippocampal neurogenesis
  • Improves cognitive performance and memory
  • Reduces anxiety and depressive behavior
  • Novel mechanism — does not act on serotonin/dopamine/GABA receptors directly
  • May help treatment-resistant depression
  • Neuroprotective effects
  • Enhances sexual desire and libido in both men and women
  • Improves arousal through central nervous system activation
  • Effective for psychological erectile dysfunction
  • Works for female sexual arousal disorder
  • May improve sexual satisfaction and intensity
  • Fast-acting — effects within 45–60 minutes
  • FDA-approved for HSDD in premenopausal women
Side Effects
  • Generally well tolerated in animal models
  • Limited human data available
  • Possible mild headache or transient mood changes at initiation
  • Injection site reactions (SC)
  • Nausea (most common — 40% of users in clinical trials)
  • Facial flushing and warmth
  • Transient blood pressure changes (typically increase then normalize)
  • Headache
  • +2 more
Stacks With