Growth Hormone SecretionStrong Evidence

Mk-677 (ibutamoren) Peptide Therapy

Benefits, Side Effects, Cost & Protocols

Mk-677 (ibutamoren) peptide molecular structure diagram from PubChem

Ibutamoren (MK-677) is a potent, long-acting, orally-active, selective, and non-peptide agonist of the ghrelin receptor and a growth hormone secretagogue. It has been shown to increase secretion of GH and insulin-like growth factor 1 (IGF-1) and produces sustained increases in plasma levels of these hormones.

ByChris Riley(CFA)&Alex Evans, PharmD, MBA(PharmD, MBA)|Updated May 19, 2026

Clinically Reviewed

Reviewed by Alex Evans, PharmD, MBA · Updated May 2026

Evidence-Based

Sourced from FDA, PubMed & ClinicalTrials.gov · View sources

FDA Status

Research Only Not currently approved for human use in the US. Available as a research compound. Not eligible for compounding.

Evidence

Strong Evidence

How Mk-677 (ibutamoren) Works

Mimics ghrelin at the GHS-R1a receptor, stimulating pulsatile GH release from the pituitary. Increases IGF-1 levels without significantly affecting cortisol or prolactin.

Mk-677 (ibutamoren) FAQ

What is MK-677 (IBUTAMOREN)?

MK-677 (Ibutamoren) is a potent, orally active growth hormone secretagogue that mimics ghrelin signaling to stimulate GH and IGF-1 release without affecting cortisol levels.

How does MK-677 (IBUTAMOREN) work?

Mimics ghrelin at the GHS-R1a receptor, stimulating pulsatile GH release from the pituitary. Increases IGF-1 levels without significantly affecting cortisol or prolactin.

Is MK-677 (IBUTAMOREN) legal to buy?

MK-677 (IBUTAMOREN) is sold as a research chemical for laboratory use only. It is not approved for human use by the FDA. Regulations vary by jurisdiction.

Where can I buy MK-677 (IBUTAMOREN)?

MK-677 (IBUTAMOREN) is available as a research compound from verified online vendors. Always verify third-party testing before purchasing.

What category does MK-677 (IBUTAMOREN) belong to?

MK-677 (IBUTAMOREN) is primarily classified as a growth hormone secretion peptide. Peptides that stimulate or support growth hormone release, including GHRH analogs, GHRPs, and direct GH compounds for muscle, recovery, and anti-aging research.

What are the research benefits of MK-677 (IBUTAMOREN)?

MK-677 (IBUTAMOREN) has been studied for: Growth hormone release, IGF-1 elevation, Improved sleep quality, Muscle mass support, Bone density support. Oral GH secretagogue; technically a small molecule, commonly grouped with peptides.

Key Studies

105 total on PubMed72 human trials

Growth hormone secretagogue MK-677: no clinical effect on AD progression in a randomized trial

Sevigny JJ, Ryan JM, van Dyck CH et al

NeurologyPhase 3

MK-677 increased IGF-1 but showed no effect on Alzheimer disease progression.

MK-677 increased IGF-1 but showed no effect on Alzheimer disease progression

MK-0677 (ibutamoren mesylate) for the treatment of patients recovering from hip fracture: a multicenter, randomized, placebo-controlled phase IIb study

Adunsky A, Chandler J, Heyden N et al

Arch Gerontol Geriatr · Arch Gerontol GeriatrPhase 2

MK-0677 improved gait speed but not most functional measures; trial terminated early due to safety concerns.

MK-0677 improved gait speed but not most functional measures; trial terminated early due to safety concerns

A GH Secretagogue Receptor Agonist (LUM-201) Elicits Greater GH Responses than Standard GH Secretagogues in Subjects of a Pediatric GH Deficiency Trial

Horm Res Paediatr · Horm Res PaediatrPhase 2

LUM-201 elicited significantly greater GH responses than standard diagnostic stimuli in pediatric GH deficiency subjects

SARMs, Metabolic Modulators and Growth Hormone Secretagogues in Suspected Illegal Medicines, Bought as Sport Performance Enhancers: A Retro- and Prospective Study Within the GEON

Barrios MM, Deconinck E, Vanhee C et al

Case Series · Drug Test Anal

65% of seized SARMs/GHS products mislabeled as medicine; majority contain active/overdoses.

Mk-677 (ibutamoren) Compound Data

Molecular Formula

C27H36N4O5S

Molecular Weight

528.7 g/mol

IUPAC Name

2-amino-N-[(1R)-1-(benzyloxymethyl)-2-(1-methylsulfonylspiro[indoline-3,4'-piperidine]-1'-yl)-2-oxo-ethyl]-2-methyl-propanamide

View full compound on PubChem

Mk-677 (ibutamoren) News

The 7 Best Peptides for Muscle Growth - Hone Health

Hone Health · 16 months ago

Does MK-677 Cause Penis Growth? A Realistic Look at the Claims - Portal CNJ

Portal CNJ · 10 days ago

Peptides and Promises of Easy Recovery and Gains - Quick and Dirty Tips

Quick and Dirty Tips · 20 months ago

Does HGH cause erectile dysfunction? - stat.gov.pl

stat.gov.pl · 1 day ago

Sermorelin vs. MK-677: Research Uses - Technology Org

Technology Org · 25 months ago

News aggregated via Google News. Inclusion does not imply endorsement.

Medical Disclaimer: The information on this page is for educational purposes only and does not constitute medical advice. Peptide therapies have not been evaluated by the FDA for most listed indications.All prices shown are estimates based on publicly available data and may not reflect current pricing — providers and brands set their own prices and can change them at any time. Always verify pricing directly with the provider before purchasing. Consult a licensed healthcare provider before starting any peptide protocol.

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