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Follistatin 344 dosage and protocol
Myostatin inhibitor that promotes muscle growth and hypertrophy. Blocks myostatin to allow increased muscle development.
- Vial size: 1 mg
- Reconstitution: 1 mL bacteriostatic water
- Concentration: 1mg/mL
- Administration: subcutaneous
Research areas
- Muscle Growth
- Myostatin Inhibition
- Anti-Fibrotic
- Regeneration
- Athletic Performance
Quick start
- Reconstitute: Add 1 mL bacteriostatic water to the 1 mg vial for 1 mg/mL
- Typical dose: 100–300 mcg per day
- Easy measuring: At 1 mg/mL, 1 unit (0.01 mL) is 10 mcg on a U-100 syringe, so 100 mcg is 10 units and 300 mcg is 30 units
- Storage: Refrigerate after mixing and use within 2–3 weeks
Dosing protocol
| Phase | Dose | Frequency | Volume |
|---|---|---|---|
| Standard | 100-300mcg | daily | 0.1-0.3 |
| Experimental | 100mcg | 1-2x daily | 0.1 |
How it works
Follistatin is a naturally occurring glycoprotein that binds and neutralizes members of the TGF-beta superfamily, most notably myostatin (GDF-8) and activin. Myostatin normally limits skeletal muscle growth by signaling through activin type II receptors and SMAD2/3. By sequestering myostatin and activin, follistatin removes this brake, allowing greater muscle fiber growth and satellite-cell activity. FS344 refers to the 344-amino-acid precursor that is processed into the circulating FS315 isoform. Animal research shows strong effects: mice overexpressing follistatin or lacking myostatin develop markedly increased muscle mass. Gene therapy using an adeno-associated virus carrying the FS344 gene increased muscle size and strength in mice and primates, and small early-phase human gene-therapy trials in Becker muscular dystrophy and inclusion body myositis reported improvements in walking distance in some participants. Those human results used gene delivery, not injection of the protein. Follistatin is a large protein (roughly 35 kDa) that is difficult to produce correctly, and there are no published trials of injected follistatin peptide for muscle growth. The activity and authenticity of research-market products are uncertain. Because activin also regulates reproductive hormones such as FSH, blocking it may have effects beyond muscle.
Reconstitution steps
- Draw 1.0 mL bacteriostatic water with a sterile syringe
- Inject slowly down the vial wall; avoid foaming
- Gently swirl/roll until dissolved (do not shake)
- Label with reconstitution date and refrigerate at 2–8°C, protected from light; use within 2–3 weeks
Storage
Store reconstituted peptide refrigerated. Use within 2-3 weeks when refrigerated.
Important notes
- Binds to and inhibits myostatin activity
- Promotes muscle hypertrophy and regeneration
- Also plays roles in inflammation and fibrosis reduction
- Human data limited - risk of overgrowth or organ/off-target effects if misused
- Not approved for human consumption
- Research settings only
Supplies
- Bacteriostatic water
- Insulin syringes
- Alcohol swabs