Triptorelin vs Follistatin 315
Side-by-side comparison of key properties, dosing, and research.
Sexual Health & Libido
TriptorelinAnabolic & IGF
Follistatin 315- Summary
- Triptorelin is a synthetic decapeptide analog of gonadotropin-releasing hormone (GnRH) with 100x the potency of native GnRH. An FDA-approved drug (Trelstar) for prostate cancer and precocious puberty, it is also used in post-cycle therapy (PCT) to rapidly restart the hypothalamic-pituitary-gonadal (HPG) axis after anabolic steroid suppression.
- 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.
- Half-Life
- Depot forms: weeks to months; aqueous: 6-8 hours
- ~3–5 hours (longer systemic circulation vs FST-344)
- Admin Route
- SubQ, IM
- SubQ, IM
- Research
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- Typical Dose
- 100 mcg
- No established human dosing protocol
- Frequency
- Single injection
- Research use only
- Key Benefits
- Rapid HPG axis restart after steroid use
- Single-injection PCT protocol possible
- Massively elevates LH and FSH via flare effect
- Restores endogenous testosterone faster than traditional PCT
- FDA-approved for established medical uses
- 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
- Side Effects
- Initial testosterone flare (intended)
- Injection site reactions
- Hot flashes (with chronic use)
- Decreased libido (chronic dosing)
- 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
- Stacks With
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