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ToolsCompareFollistatin 315 vs Dermorphin

Follistatin 315 vs Dermorphin

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

Anabolic & IGF
Follistatin 315
Recovery & Repair
Dermorphin
Summary
Follistatin 315 is a splice variant isoform of follistatin produced by alternative mRNA processing. Unlike Follistatin 344 which is tethered to cell surfaces via heparan sulfate proteoglycans, FST-315 circulates freely in the bloodstream and has broader systemic distribution. It is the predominant circulating form and exerts systemic myostatin inhibition as well as FSH suppression, making it relevant to both muscle growth and reproductive endocrinology.
Dermorphin is a naturally occurring heptapeptide opioid isolated from the skin of South American phyllomedusine frogs. It is one of the most potent endogenous mu-opioid receptor agonists known, approximately 30-40 times more potent than morphine by weight. Explored for pain management and fatigue modulation.
Half-Life
~3–5 hours (longer systemic circulation vs FST-344)
Estimated 30-60 minutes (longer than endorphins due to D-Ala)
Admin Route
SubQ, IM
Subcutaneous (research), Intrathecal (research), Intranasal (research)
Research
Typical Dose
No established human dosing protocol
Not established for human use; research doses vary widely
Frequency
Research use only
Not established
Key Benefits
  • Systemic myostatin inhibition for whole-body muscle growth
  • Freely circulating — broader tissue distribution than FST-344
  • Strong FSH-suppressive activity useful in certain hormonal protocols
  • Potential for greater anabolic effect across multiple muscle groups simultaneously
  • May be more relevant to reproductive endocrinology applications
  • Studied in gene therapy approaches for muscular dystrophy
  • Potent analgesia superior to morphine on a per-weight basis
  • May reduce perception of fatigue in high-intensity activity
  • Longer-lasting than endogenous opioids due to D-amino acid substitution
  • Research tool for mu-opioid receptor pharmacology
  • Potential therapeutic application in refractory pain
Side Effects
  • Systemic FSH suppression — significant concern for fertility
  • Greater potential for off-target effects vs FST-344 due to systemic distribution
  • Limited human safety data
  • Potential cardiac hypertrophy with prolonged high-dose exposure
  • High addiction and dependence potential (mu-opioid agonism)
  • Respiratory depression at high doses
  • Nausea, vomiting, constipation
  • Sedation and cognitive impairment
  • +2 more
Stacks With