Follistatin 344 vs Kisspeptin-10
A neutral, side-by-side comparison of two performance & growth hormone peptides — their mechanisms, dosing ranges, administration routes, side effects, and research evidence. For research and educational purposes only.
Follistatin 344
Follistatin 344 is a 344-amino acid isoform of follistatin — an endogenous glycoprotein that functions primarily as a myostatin and activin inhibitor. Myostatin (GDF-8) is the body's primary muscle growth suppressor; follistatin binds and neutralizes it with high affinity, removing this brake on muscle protein synthesis. Research and animal data show dramatic increases in muscle fiber size and strength when follistatin is elevated or myostatin is inhibited.
Full profileKisspeptin-10
Kisspeptin-10 is the biologically active 10-amino acid C-terminal fragment of kisspeptin, a neuropeptide that acts as the master regulator of the hypothalamic-pituitary-gonadal (HPG) axis. By activating KISS1R (GPR54) in the hypothalamus, it triggers pulsatile GnRH release, which drives LH, FSH, and downstream testosterone and estrogen production. It is the upstream signal that 'turns on' the reproductive axis — with research applications spanning fertility, hypogonadism, post-cycle therapy support, and age-related hormonal decline.
Full profile| Follistatin 344 | Kisspeptin-10 | |
|---|---|---|
| Category | Performance & Growth Hormone | Performance & Growth Hormone |
| Also known as | FST-344, Follistatin isoform 344, FST | KP-10, Metastin(112-121), KISS1R agonist |
| Evidence | Research-stage | FDA-approved |
| Dosing range | 50mcg–200mcg mcg, Once daily or every other day for 10–30 day cycles | 50mcg–250mcg mcg, 1–2x daily (pulsatile administration is important — avoid continuous infusion) |
| Administration | Subcutaneous injection, Intramuscular injection (into target muscle — local effect hypothesis) | Subcutaneous injection, Intranasal, Intravenous (clinical studies — produces most reliable LH pulses) |
| Key side effects | Potential FSH suppression (reproductive effects in females — may affect menstrual cycle), Accelerated hair follicle cycling (Wnt pathway involvement — theoretical hair loss concern at high doses), Joint discomfort with rapid muscle tissue growth, Limited long-term human safety data | Generally well-tolerated in clinical trials, Nausea (mild, uncommon), Potential for over-stimulation of the HPG axis at high doses (rarely significant), Theoretical desensitization with continuous (non-pulsatile) dosing |
| Cited sources | 3 references | 3 references |
Key differences
- Evidence level differs: Follistatin 344 is research-stage, while Kisspeptin-10 is fda-approved.
- Administration: Follistatin 344 — Subcutaneous injection, Intramuscular injection (into target muscle — local effect hypothesis); Kisspeptin-10 — Subcutaneous injection, Intranasal, Intravenous (clinical studies — produces most reliable LH pulses).
- Frequency: Follistatin 344 is typically Once daily or every other day for 10–30 day cycles; Kisspeptin-10 is 1–2x daily (pulsatile administration is important — avoid continuous infusion).
How each works
Follistatin 344
Follistatin's muscle effects were dramatically illustrated when mice and cattle with follistatin overexpression or myostatin knockouts developed 2–3x normal muscle mass. Human follistatin gene therapy trials (AAV-mediated) are ongoing for Becker Muscular Dystrophy, showing sustained myostatin inhibition and improved muscle function over years from a single injection. Follistatin also inhibits activin A and B (involved in muscle wasting during illness), FSH secretion (reproductive effects), and inflammatory cytokines. The 344 isoform has an extended heparin-binding domain that increases tissue retention compared to the shorter FST-288 isoform.
Kisspeptin-10
Kisspeptin neurons in the arcuate nucleus form the pulse generator for GnRH secretion — without kisspeptin signaling, reproductive function ceases. Human clinical trials confirm that IV kisspeptin-10 produces rapid, dose-dependent LH pulses in both males and females, restoring hormonal function in hypogonadotropic hypogonadism. Kisspeptin-54 (the longer form) has been studied in human fertility treatments with successful outcomes. Unlike direct LH/FSH administration, kisspeptin works upstream at the hypothalamus, preserving the natural pulsatile release pattern and avoiding receptor desensitization associated with continuous GnRH agonists.
This comparison aggregates public research and structured profile data for informational purposes only. It is not medical advice and does not recommend either compound for human use. Consult a qualified healthcare provider before considering any peptide.