Index/Follistatin 344Muscle & Performance

FOLLISTATIN 344

FST-344 · Follistatin

Myostatin inhibitor — significant lean mass increases.

FDA

Research Only

WADA

Banned

HALF-LIFE

~3–4 hours

ROUTE

IM injection

SCHEDULE

Daily or every other day

In Plain English

Myostatin inhibitor — significant lean mass increases.

Status & Legality

NATTY?

Not Natty

WADA banned substance. Tested athletes will fail.

FDA

Research Only

For research purposes only. Not FDA approved.

WADA

Banned

On WADA prohibited list. Use disqualifies in tested sports.

COMPOUNDING

Not from pharmacies

Not available from licensed compounding pharmacies.

PRESCRIBED

Not prescribed

Not prescribed in conventional medicine.

ROUTE

IM injection

Administration via im injection.

Who It's For

Myostatin inhibition

Lean mass gain

Muscle endurance

Strength

How It Works

Follistatin-344 is a glycoprotein that binds and inhibits myostatin — the primary negative regulator of muscle growth. By blocking myostatin, it removes the genetic 'brakes' on muscle development. Studies show significant increases in muscle mass with minimal fat gain. Highly sought after in performance communities.

Side Effects

01

Hypoglycemia

02

Muscle soreness

03

Potential tumor promotion (theoretical)

04

Joint discomfort

05

Headache

Common Mistakes

Insufficient protein intake — myostatin inhibition creates the opportunity for growth; protein provides the building material; without ≥1.5 g/kg, results are blunted

Running continuously without cycling — 30-day maximum cycles are standard; longer continuous use may impair muscle quality markers

Expecting dramatic changes in weeks — Follistatin cycles produce meaningful results over 4–8 weeks; impatience leads to inappropriate dose escalation

Drug & Supplement Interactions

IGF-1 LR3 — synergistic; myostatin blockade + direct IGF-1 receptor stimulation for comprehensive anabolic effect

Anabolic steroids — potent combination; experienced guidance required due to compounded effects

GH secretagogues — additive growth factor signaling; monitor for adverse effects at high doses

The PepVault Take

Follistatin 344 removes the genetic ceiling on muscle growth by blocking myostatin — the body's primary brake on muscle development. The results are significant and well-documented in the performance community. It sits firmly in the 'advanced' category: potency, limited safety data, and WADA-banned status mean experienced guidance and careful cycling are mandatory.

Frequently Asked Questions

Stats

ONSET50
DOCUMENTATION18
SIDE INTENSITY60
CYCLE EASE60
POPULARITY25
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Research Use OnlyNot Medical AdviceNot FDA Evaluated18+ OnlyWADA Status Tracked

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