Follistatin-344
Animal / preclinicalWADA prohibitedAlso known as: FS-344
Community-reported ranges are anecdotal and not clinically validated. Evidence grade shown reflects the strength of available human data. Not a prescription. Legal status varies by country and changes over time; verify locally.
Overview
A form of follistatin, the body's natural myostatin blocker. Gene-therapy and animal studies produced dramatic muscle growth — the famous 'double-muscled' phenotypes — which is the draw; whether an injected peptide product reproduces any of that in humans is untested, and it falls under WADA's myostatin-related prohibitions.
Mechanism
Binds myostatin (and related TGF-β family members), releasing the brake on muscle growth in animal models.
Evidence
Dramatic animal and gene-therapy results are real; an injected peptide product is a different delivery question, untested in humans, and systemic myostatin inhibition has theoretical trade-offs.
Community-reported information
Community reports vary. Anecdotal, unvalidated and potentially risky; general information only.
General information only, not tailored to you and not a recommendation. Some regions withhold this entirely.
Half-life
Not well characterised for injectable use in humans.
Storage
Refrigerate; sensitive to degradation.
Commonly reported side effects
- Not well characterised in humans
Legal status by region
- USNot FDA-approved for human use.
- AUPrescription-only; import controlled.
Legal status changes over time; verify locally before relying on this.