--- title: "Follistatin-344: Dosage & Side Effects | BodyHackGuide" url: https://www.bodyhackguide.co/compound/follistatin-344 description: "Follistatin-344: dosing protocols, mechanism & side effects, 924 PubMed results." lang: en --- Skip to content Compare notes on r/BodyHackGuide (https://reddit.com/r/bodyhackguide) Compare notes with other researchers. Join r/BodyHackGuide (https://reddit.com/r/bodyhackguide) # Follistatin-344 Myostatin Inhibitor: https://www.bodyhackguide.co/wiki#cat-myostatin-inhibitor Status Preclinical / Research peptide,, not approved for human use Evidence Small human trials, mixture and gene therapy only, graded on 2 research benches Follistatin-344 is named for the 344-amino-acid precursor of follistatin [PMID:3380788]; once its 29-residue signal peptide is removed, the mature glycoprotein (FST-315) is 315 residues long (UniProt P19883). Reviewed 2 October 2026 01 Overview ## What Follistatin-344 is Follistatin binds and neutralizes myostatin (GDF-8) - the primary negative regulator of skeletal muscle growth. Originally isolated from porcine ovarian fluid in the 1980s, the synthetic peptide form has become a research compound for studying myostatin antagonism and skeletal muscle hypertrophy. Naturally occurring follistatin forms (the mature FS288 and FS315, made from the 317- and 344-residue precursors; UniProt P19883) differ in tissue distribution and serum half-life. The 344 variant is the most-studied for muscle research. Knockout mouse models lacking myostatin (or with high follistatin expression) show 2-3x normal muscle mass. ### How it works Follistatin binds and sequesters myostatin (GDF-8), preventing myostatin from activating the activin-receptor-mediated signaling pathway that normally suppresses muscle growth. Without myostatin signaling, satellite cells proliferate more aggressively, myoblast fusion is enhanced, and muscle protein synthesis exceeds catabolism. Follistatin also binds activin A and other TGF-beta family members, broadening its inhibition profile beyond myostatin alone. Note: the satellite-cell proliferation and muscle-protein-synthesis effects described above reflect follistatin's established molecular mechanism and its preclinical (cell-culture and animal) biology; they have not been demonstrated for the injectable Follistatin-344 research peptide in humans, for which no controlled efficacy or pharmacokinetic data exist. ### Studied for - Muscle hypertrophy - Myostatin biology - Sarcopenia - Muscular dystrophy - TGF-beta family ### Benefits listed - Myostatin antagonism for skeletal muscle growth - Satellite cell proliferation enhancement - Activin-A binding (broader TGF-beta family inhibition) - Research into muscular dystrophy and sarcopenia 02 Research Free with email ## What the research shows ### Graded on 2 research benches Reference pages that put Follistatin-344 next to the compounds people pair it with: roles, evidence, overlap and conflicts. No dosing. Research use only. - Peptides for Hair Growth Small human trials, mixture and gene therapy only human data on 4 of 6 compounds on the bench: https://www.bodyhackguide.co/stack/hair-growth-peptides - Peptides for Muscle Growth No human trials of the protein human data on 4 of 6 compounds on the bench: https://www.bodyhackguide.co/stack/muscle-growth-peptides ### Unlock the research summary Enter your email to keep reading. It is free, and it opens these sections on every compound page in this browser. - A summary of the key research - Safety and side effects - A link to the PubMed results You also get the free peptide cheat sheet by email. Unsubscribe anytime. Have an account? Sign in (https://www.bodyhackguide.co/auth) 03 Safety ## Follistatin-344 side effects and interactions ### Side effects #### Common - Injection site irritation (anecdotal) - Mild water retention (anecdotal) - Transient soreness in trained muscles (anecdotal) #### Serious events - Theoretical cardiac hypertrophy with prolonged use - Off-target TGF-beta inhibition affecting wound healing - Long-term human safety data unavailable ### Who should not use it Contraindications Active malignancy. Pregnancy and breastfeeding. Cardiomyopathy or left ventricular hypertrophy. Active wound healing or post-surgical recovery (TGF-beta inhibition concerns). Prohibited in sport. The World Anti-Doping Agency 2026 Prohibited List, in force from 1 January 2026, lists myostatin-binding proteins including follistatin under section S4.3, agents preventing activin receptor IIB activation. ### Interactions Not in our record Our record lists no interactions for Follistatin-344. That means none are recorded here, not that none exist. This interaction data is compiled from published research and community reports. It may not be exhaustive. Always consult a healthcare professional before combining compounds. Need bloodwork before starting? Full hormone + metabolic panels from Anabolic Insights. Code CHONCH for first-order discount. Order Bloodwork (https://anabolicinsights.ai/?ref=nwm2zjb) 04 Dosing Free with email ## Follistatin-344 dosage and protocols Dose range 50-100 mcg Dosing Once daily Common vials 1mg, 2mg, 5mg ### Unlock the dosing protocols - Dose, route, how often and how long - Beginner, intermediate and advanced protocols - Reconstitution and handling notes - Stacking notes 05 Prices ## Follistatin-344 prices No listings We do not track a vendor for Follistatin-344 yet, so this page states no price. 06 Chemistry ## Chemistry and structure Molecular formula Glycoprotein (~37 kDa) Molecular mass ~38 kDa glycosylated (mature FST-315 glycoprotein); ~35 kDa for the unglycosylated ~315-residue core. A large glycoprotein, not a small peptide. Amino acid sequence Follistatin-344 is a 344-residue precursor protein (29-residue signal peptide + 315-residue mature chain; isoform FST-315, human UniProt P19883), not a short synthetic peptide. The mature glycoprotein comprises an N-terminal domain plus three follistatin domains and is N-glycosylated, so a simple linear peptide sequence is not the relevant descriptor. Half-life Short; native follistatin protein is cleared rapidly (minutes to a few hours in vivo). No formal pharmacokinetic data exist for injected Follistatin-344 (FST-344). 07 Related ## Related to Follistatin-344 ### Compare Follistatin-344 - Alternatives to Follistatin-344: https://www.bodyhackguide.co/alternatives-to/follistatin-344 ### Research tools - Peptide Calculator Reconstitution and syringe units: https://www.bodyhackguide.co/tools/reconstitution - Reconstitution Guide How to mix, step by step: https://www.bodyhackguide.co/guides/how-to-reconstitute-peptides - Nasal Spray Calc mL per actuation: https://www.bodyhackguide.co/tools/intranasal - Half-Life Visualizer Decay curves: https://www.bodyhackguide.co/tools/halflife All articles (https://www.bodyhackguide.co/blog) 08 Questions ## Frequently asked questions What is Follistatin-344 used for in research? Follistatin-344 is named for the 344-amino-acid precursor of follistatin [PMID:3380788]; once its 29-residue signal peptide is removed, the mature glycoprotein (FST-315) is 315 residues long (UniProt P19883). Follistatin binds and neutralizes myostatin (GDF-8) - the primary negative regulator of skeletal muscle growth. Originally isolated from porcine ovarian fluid in the 1980s, the synthetic peptide form has become a research compound for studying myostatin antagonism and skeletal muscle hypertrophy. What forms does Follistatin-344 come in? Follistatin-344 is available in vials, capsules, and sprays forms. How much does Follistatin-344 cost? BodyHackGuide tracks no vendor for Follistatin-344 yet, so no price is stated. How do I compare Follistatin-344 vendors? Compare prices, payment methods, shipping, and COA scores across 0 vendors. Free 2026 Peptide Cheat Sheet (PDF) 38 compounds and blends: vial sizes, BAC water volumes, dosing ranges and bloodwork markers. Download Free (https://www.bodyhackguide.co/guides/peptide-cheat-sheet-download) BodyHackGuide (https://www.bodyhackguide.co/) Your biohacking research hub: compound pricing, brain health protocols, dosing tools, and vendor reviews. support@bodyhackguide.co Join our Discord: https://discord.gg/Mhq5UdRYBA r/BodyHackGuide on Reddit: https://reddit.com/r/BodyHackGuide **Affiliate Disclosure:** We rank every vendor on the same public, reproducible methodology (https://www.bodyhackguide.co/vendors/methodology). Full details in our affiliate disclosure (https://www.bodyhackguide.co/affiliate-disclosure). **Research Disclaimer:** All compounds listed are for laboratory and research purposes only. Not for human consumption. This site does not sell or ship any products. Always consult a qualified healthcare professional and comply with local regulations. © 2026 BodyHackGuide. All rights reserved. - Terms: https://www.bodyhackguide.co/terms - Privacy: https://www.bodyhackguide.co/privacy ## Structured data ```json [ { "@context": "https://schema.org", "@type": "BreadcrumbList", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "Home", "item": "https://www.bodyhackguide.co/" }, { "@type": "ListItem", "position": 2, "name": "Compounds", "item": "https://www.bodyhackguide.co/compare" }, { "@type": "ListItem", "position": 3, "name": "Follistatin-344" } ] }, { "@context": "https://schema.org", "@type": "MedicalWebPage", "name": "Follistatin-344", "description": "Follistatin-344 is named for the 344-amino-acid precursor of follistatin [PMID:3380788]; once its 29-residue signal peptide is removed, the mature glycoprotein (FST-315) is 315 residues long (UniProt P19883). Follistatin binds and neutralizes myostatin (GDF-8) - the primary negative regulator of skeletal muscle growth. Originally isolated from porcine ovarian fluid in the 1980s, the synthetic peptide form has become a research compound for studying myostatin antagonism and skeletal muscle hypertrophy. Naturally occurring follistatin forms (the mature FS288 and FS315, made from the 317- and 344-residue precursors; UniProt P19883) differ in tissue distribution and serum half-life. The 344 variant is the most-studied for muscle research. 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Follistatin binds and neutralizes myostatin (GDF-8) - the primary negative regulator of skeletal muscle growth. Originally isolated from porcine ovarian fluid in the 1980s, the synthetic peptide form has become a research compound for studying myostatin antagonism and skeletal muscle hypertrophy. Naturally occurring follistatin forms (the mature FS288 and FS315, made from the 317- and 344-residue precursors; UniProt P19883) differ in tissue distribution and serum half-life. The 344 variant is the most-studied for muscle research. Knockout mouse models lacking myostatin (or with high follistatin expression) show 2-3x normal muscle mass.", "activeIngredient": "Follistatin-344", "administrationRoute": "Subcutaneous, Intramuscular", "mechanismOfAction": "Follistatin binds and sequesters myostatin (GDF-8), preventing myostatin from activating the activin-receptor-mediated signaling pathway that normally suppresses muscle growth. Without myostatin signaling, satellite cells proliferate more aggressively, myoblast fusion is enhanced, and muscle protein synthesis exceeds catabolism. Follistatin also binds activin A and other TGF-beta family members, broadening its inhibition profile beyond myostatin alone. Note: the satellite-cell proliferation and muscle-protein-synthesis effects described above reflect follistatin's established molecular mechanism and its preclinical (cell-culture and animal) biology; they have not been demonstrated for the injectable Follistatin-344 research peptide in humans, for which no controlled efficacy or pharmacokinetic data exist.", "legalStatus": "Not approved for human use (research chemical)", "warning": "For research purposes only. 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