Research use only.  Educational reference. Not medical advice. Not for human consumption.
💪 Myostatin Inhibitor

FST 344 (Follistatin) (1 mg Vial) Dosage Protocol

Follistatin (FST 344) is a glycoprotein that inhibits myostatin and activin, studied for muscle growth and tissue repair.

⚡ Quickstart Highlights

Vial size
1 mg
Reconstitution
3 mL BAC water → 0.33 mg/mL
1 U-100 unit =
3.3 mcg
Frequency
2–3× weekly

Dosing & Reconstitution Guide

Route: Subcutaneous  |  Frequency: 2–3× weekly  |  Half-life: ~12 hours

Standard Approach (3 mL = 0.33 mg/mL)

Reconstituting with 3 mL bacteriostatic water produces a concentration of 0.33 mg/mL. Volume per dose changes with concentration; mg dose itself does not change between vial sizes.

Phase / ProtocolDoseU-100 UnitsVolumeDoses per vial
Standard100 mcg30.0 units0.30 mL10 doses

Reconstitution Steps

  1. Wipe the vial stopper and BAC water vial with alcohol; let dry.
  2. Draw 3 mL of bacteriostatic water into a sterile syringe.
  3. Inject slowly down the inside glass wall of the peptide vial. Do not aim at the powder.
  4. Gently swirl until fully dissolved. Do not shake.
  5. Label with reconstitution date. Refrigerate at 2–8°C; use within 14 days.

Supplies Needed

Estimates for an 8-week and 12-week cycle at 100 mcg per dose, 2–3× weekly (3 doses/week).

Item8-Week Cycle12-Week Cycle
FST 344 (Follistatin) (1 mg) vials3 vials4 vials
Insulin syringes (U-100)2436
Bacteriostatic water (10 mL)1 × 10 mL2 × 10 mL
Alcohol swabs1 × 100-pack2 × 100-pack

Protocol Overview

Follistatin (FST 344) suppresses myostatin, removing the natural brake on skeletal muscle hypertrophy. Effects compound during active training cycles — solo dosing without resistance training produces minimal benefit.

WADA prohibited list. Long-term safety data is limited.

Dosing Protocol

Twice-to-three-times-weekly dosing:

Cycle structure: 6–8 weeks active training cycle, then 8–12 week break. Conservative cycling given limited long-term data.

Timing: Within 1 hour post-training, sub-Q near target muscle group.

Storage Instructions

StateTemperatureDuration
Lyophilized−20°C (−4°F)Up to 24 months, dry & dark
Reconstituted2–8°C (35–46°F)Up to 14 days, protect from light

Important Notes

⚠ Research Use Only: WADA prohibited.

How This Works

Follistatin is a glycoprotein that binds and neutralizes myostatin (a muscle growth inhibitor) and activin. By suppressing myostatin, follistatin removes the brake on satellite cell activation and skeletal muscle hypertrophy. Knockout and overexpression studies show dramatic muscle phenotype changes.

Potential Benefits & Side Effects

Potential Benefits

Side Effect Profile

Lifestyle Factors

Injection Technique

References

1
Lee SJ. 'Quadrupling muscle mass in mice by targeting TGF-β signaling pathways' — PLoS One, 2007 View source ↗