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eHealthTutorial — Research Peptide Reviews
Investigational small molecule • FDA safety caution

Oral ghrelin-mimetic research

MK-677 (Ibutamoren)

MK-677, or ibutamoren, is an oral ghrelin-receptor mimetic, not a peptide. A controlled study in older adults increased hormone biomarkers and fat-free mass without improving strength or function.

Generic research visual — not a commercial product
Compound typeNon-peptide oral small molecule
Evidence baseSmall controlled human trials
Regulatory contextInvestigational / Not FDA-approved
Page purposeResearch overview
Why there is no compound calculator on this page

The studied MK-677 was an oral small molecule, not a generic peptide powder for syringe reconstitution. FDA highlights a potential congestive-heart-failure safety signal for ibutamoren mesylate.

Research overview

What is MK-677 (Ibutamoren)?

Ibutamoren is a non-peptide small-molecule agonist of the ghrelin/growth-hormone secretagogue receptor. It is commonly catalogued with peptides but its chemical class and studied oral delivery are different. It is not a substitute for prescription growth hormone.

What has research examined?

A randomized modified-crossover trial in 65 healthy older adults found increased GH/IGF-I and fat-free mass with studied oral MK-677, but no increase in strength or function and no significant reduction in visceral fat. Fasting glucose increased and insulin sensitivity decreased. FDA notes that a separate hip-fracture-recovery trial was terminated early over a possible congestive-heart-failure safety signal.

Important limitation

Biomarker and body-composition measurements are not an anti-aging or performance treatment demonstration. Heart-failure and glucose concerns require more than a supplier label; no amount or use advice is offered.

Research references

Calculation boundary

The studied MK-677 was an oral small molecule, not a generic peptide powder for syringe reconstitution. FDA highlights a potential congestive-heart-failure safety signal for ibutamoren mesylate.

For research purposes only. This page is educational and is not medical or veterinary advice or a recommendation to purchase, prepare, administer, or use any product.