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Follistatin 344
Growth Factors & Muscle BuildingFollistatin 344 (FS344) is a potent myostatin inhibitor that promotes muscle hypertrophy and strength by suppressing GDF-8 and activin pathways. It is explored in gene and peptide therapies for muscle-wasting diseases and performance enhancement. Human safety and regulatory pathways are still under evaluation.
Reconstitute
1 mL BAC + 1mg vial
10 mcg/unit
Daily Range
0.5–2 mg Subcutaneous (SQ)
Weekly
Standard Dose
1 mg
Cycle
4–8 weeks
then reassess
Follistatin 344myostatin inhibitormuscle growthFS344gene therapy
Dosing & Reconstitution Guide
In research settings, Follistatin 344 is commonly dosed at 100–200 mcg, 2–3 times per week, depending on species and study design. These regimens are investigational and do not represent approved human protocols.
Standard / Gradual Approach
1mg VialstandardPhaseDoseVolume
Week 1100mcg
Week 2150mcg
Week 3200mcg
Week 4250mcg
Protocol Summary
Subcutaneous (SQ): Weekly · Dose range 0.5–2 mg with gradual titration
Cycle Length: 4–8 weeks typical; reassess before extending
Frequency & Cycling
SubQ Injection
Inject 1–2 mg SubQ every 3–4 days for 4–6 weeks. Recommended 6+ week break afterward to avoid suppression feedback from prolonged myostatin blockade.
🧪 Quick Start
Vial Size
1 mg
BAC Water
1 mL
Concentration
1000 mcg/unit
Potential Benefits & Use Cases
Follistatin 344 is a research-use-only compound. It is not approved for human or veterinary use. All information provided is for scientific and educational reference only.
Inhibits myostatin and activin A (members of the TGF-β superfamily)
Studied for promoting muscle fiber hypertrophy in rodent models
Explored for reducing fibrosis and improving tissue remodeling
May support cartilage protection and tendon recovery in preclinical settings
Investigated for potential synergy with growth hormone and IGF-1 in animal research
Clinical data Strong preclinical Limited data
Mechanism of Action
→Binds to and inhibits myostatin (GDF-8)
→Disrupts activin receptor signaling to allow for muscle hypertrophy
→Promotes satellite cell activation and muscle fiber repair
Lifestyle & Optimization
timing
Inject SubQ. Consistent timing.
diet
High protein intake (1.2–1.5g per pound body weight). Eat in caloric surplus (300–500 calories above maintenance).
exercise
Aggressive resistance training program 5–6 days per week.
sleep
Prioritize 7–9 hours of sleep nightly.
Peptide Research & Preclinical Studies
Evidence-Based Research Findings
Side Effects & Safety
Common Side Effects
• Injection site reactions
Contraindications & Warnings
• Potential adverse effects on reproductive hormone signaling
• Limited human clinical safety data
Long-Term Safety Data
• Unknown long-term impact on endocrine or cardiac systems
🧮 Dose Calculator
Concentration
10.0
mcg/unit
Draw Volume
50
units (0.500 mL)
For a 500 mcg dose, draw 50 units on a U-100 insulin syringe
🧬
Bioavailability & Absorption
SubQ Injection
Good bioavailability via subcutaneous injection with systemic exposure
Oral Administration
Low; rapidly degraded in GI tract
Half-Life
Approx. 4 hours
Degradation
Degraded by hepatic and tissue proteases
Tissue Specificity
Preferentially acts on muscle and reproductive tissues
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Peptide Details
Molecular Weight
38200
Formula
C1563H2529N419O448S8
Sequence
N/A for FS344
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Legal Status & Regulatory
RegionStatus
FDANot Approved
EUNot Approved
AustraliaNot Approved
CanadaNot Approved
Storage Instructions
Lyophilized (Powder)
Store lyophilized powder at 2-8°C
Reconstituted (Mixed)
After reconstitution, maintain at 2-8°C and use within 10-14 days. Follistatin 344 is relatively unstable; minimize storage duration.