Follistatin-344
The body’s own myostatin blocker. Follistatin-344 is the longer form that is processed into the circulating protein; it is sold as a research protein for muscle growth.
Not approved; human data come only from gene-therapy trials, not injected protein.
Used for
- Muscle growth
- Muscle-wasting diseases (gene therapy research)
How it works
Binds and neutralizes myostatin (the brake on muscle growth) and activin. Activin also drives FSH, so follistatin can lower it: the protein is named for suppressing FSH.
What the research shows
- Gene therapy (the follistatin-344 gene injected into thigh muscles) improved 6-minute walk distance in 4 of 6 men with Becker muscular dystrophy, with no serious side effects.
- The same approach improved walking in a small inclusion body myositis trial compared with untreated patients.
- No human studies of injected follistatin protein; it is a large protein, so what research vials contain and how much survives is uncertain.
Dosing
Dosing isn’t listed on the public site. In the app, each published option is shown with its source (a drug label, a clinical guideline, a trial or community reports) and can be turned into a protocol you review.
Work out the units to draw for your vial →Side effects
- Injection-site reactions
- Few reported otherwise
Cautions
- Can lower FSH and affect fertility (activin blocking).
- Strong growth signaling: avoid with cancer or a history of it.
- Prohibited in tested sports (WADA).
- Research-chemical vials have no quality control: purity, dose and sterility vary. Third-party testing helps but is no guarantee.
Storage
Unmixed powder: freezer or fridge, away from light.
Once mixed with bacteriostatic water: fridge; the common rule is to use it within 28 days.
There is no label or published stability data for this one, so treat these as habits, not limits.
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Reference only, not medical advice. Written for this app from the cited research. Doses marked community-reported are not from trials.