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Follistatin 344 vs MK-677 (Ibutamoren)
Follistatin 344 sits in muscle / growth, while MK-677 (Ibutamoren) sits in growth hormone — so despite being mentioned together they are used for different things. A mixed vial also keeps differently: about 30 days for Follistatin 344 against 60 for MK-677 (Ibutamoren). The table below sets out the differences. We give no dosing guidance.
Side by side, in plain English — what each one is, where they overlap and where they genuinely differ.
Follistatin 344Muscle / Growth
MK-677 (Ibutamoren)Growth HormoneAt a glance
| Follistatin 344 | MK-677 (Ibutamoren) | |
|---|---|---|
| Category | Muscle / Growth | Growth Hormone |
| Typical route | SubQ (or IM at site) | Oral |
| Shelf life once mixed | ~30 days | ~60 days |
| Commonly reported effects | Muscle growth Reduced myostatin Fat loss | Sustained GH/IGF-1 elevation Appetite increase Deeper sleep |
| Reported considerations | Joint pain Possible organ growth if abused | Water retention Lethargy Insulin resistance |
The differences that actually matter
They aren't really substitutes: Follistatin 344 sits in Muscle / Growth while MK-677 (Ibutamoren) sits in Growth Hormone. People usually pick between them because of a shared secondary effect rather than because they do the same job.
Route of administration differs — Follistatin 344 is typically subq (or im at site), MK-677 (Ibutamoren) is typically oral. That alone changes how convenient each one is to keep up with.
Once reconstituted, MK-677 (Ibutamoren) keeps noticeably longer than Follistatin 344 (~60 days vs ~30 days), so vial waste is a real difference between the two.
Reported mainly for Follistatin 344: muscle growth, reduced myostatin, fat loss.
Reported mainly for MK-677 (Ibutamoren): sustained gh/igf-1 elevation, appetite increase, deeper sleep.
What Follistatin 344 is
Follistatin 344 is a naturally occurring glycoprotein, with this specific isoform being a potent antagonist of myostatin. Myostatin is a growth differentiation factor belonging to the TGF-beta superfamily, primarily known for inhibiting muscle growth. Follistatin 344 binds directly to myostatin, thereby preventing myostatin from interacting with its receptors on muscle cells and signaling pathways that limit muscle development. This inhibition consequently reduces myostatin's negative regulatory effect, allowing fo
What MK-677 (Ibutamoren) is
MK-677, also known as Ibutamoren, functions as a non-peptide ghrelin receptor agonist, specifically targeting the growth hormone secretagogue receptor type 1a (GHSR-1a). By mimicking the action of endogenous ghrelin, it stimulates the pituitary gland to increase the pulsatile secretion of growth hormone (GH). This mechanism leads to sustained elevations of both GH and insulin-like growth factor 1 (IGF-1) levels in the body, typically over a 24-hour period due to its approximate 24-hour half-life. It operates by enh
How to compare them for yourself
Anecdotes online are noisy because nobody is measuring the same thing. The only comparison that means anything is your own: log each entry with a timestamp, keep the vial ledger honest so you know what you actually got through, pick two or three metrics before you start, and look at the trend after several weeks rather than day to day.
Peptide Wizard does that part for you — Follistatin 344 and MK-677 (Ibutamoren) are both in the built-in reference library with a 3D vial, and your history, vial ledger and cost per entry stay private on your device.
FAQ
What is the difference between Follistatin 344 and MK-677 (Ibutamoren)?
They aren't really substitutes: Follistatin 344 sits in Muscle / Growth while MK-677 (Ibutamoren) sits in Growth Hormone. People usually pick between them because of a shared secondary effect rather than because they do the same job.
Can you log Follistatin 344 and MK-677 (Ibutamoren) in the same period?
Plenty of people record more than one peptide at a time. Peptide Wizard keeps a separate vial ledger and entry history for each, so you can see exactly what overlapped and when — it does not recommend combinations or doses.
Which is better, Follistatin 344 or MK-677 (Ibutamoren)?
There isn't a universal answer — reported responses vary a lot between individuals, which is why your own log is more informative than anyone else's anecdote. Track one variable at a time and compare your own metrics over several weeks.
Is this medical advice?
No. This page is educational reference material only. It contains no dosing guidance. Speak to a qualified healthcare professional before making any decisions.
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Educational reference only. This page contains no dosing guidance and is not medical advice.