New — Free Peptide Starter Guide (2026): 13 chapters, 34 cited studies

Get it free
ToolsCompareMGF (Mechano Growth Factor) vs PT-141 (Bremelanotide)

MGF (Mechano Growth Factor) vs PT-141 (Bremelanotide)

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

Anabolic & IGF
MGF (Mechano Growth Factor)
Sexual Health & Libido
PT-141 (Bremelanotide)
Summary
MGF (Mechano Growth Factor) is a splice variant of IGF-1 that is locally produced in muscle tissue in response to mechanical damage from exercise. It activates muscle satellite cells (stem cells) to proliferate and repair damaged fibers, making it specifically targeted at exercise-induced hypertrophy.
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
Native MGF: minutes. PEG-MGF: ~3 days
2–3 hours
Admin Route
SubQ, IM
SubQ
Research
Typical Dose
200–400 mcg
0.5–1.75 mg
Frequency
1–2 times per week
As needed (not daily)
Key Benefits
  • Activates muscle satellite cells for repair and growth
  • Accelerates recovery from muscle damage
  • Synergistic with IGF-1 LR3 (different mechanisms)
  • Promotes muscle hypertrophy specifically at exercised muscles
  • Faster recovery between training sessions
  • Potential for injury repair in connective tissue
  • 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
  • Muscle soreness (satellite cell activation)
  • Injection site irritation
  • Hypoglycemia risk (modest, less than IGF-1 LR3)
  • 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