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Follistatin-344

Animal / preclinicalWADA prohibited

Also known as: FS-344

Growth-hormone secretagoguesMuscle growth via myostatin inhibition (claimed)

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, a natural protein that binds and inhibits myostatin. Studied mainly in gene-therapy and animal models for muscle growth; injectable-product claims are unproven 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

Animal / preclinicalWhat does this mean?

Thin: dramatic results in animal and gene-therapy studies do not establish that an injected peptide product is effective or safe in humans; systemic myostatin inhibition carries theoretical risks.

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.