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SARMs / Sold as SARMs (non-SARM)

315 In the index

Ibutamoren MK-677

An oral compound (also called MK-677) that tricks the body into releasing more growth hormone, studied in human trials for muscle loss, sleep, and frailty in older adults. Trials confirm it raises growth hormone and improves muscle mass, but it consistently increases appetite, causes fluid retention, and makes the body slightly less sensitive to insulin.

Also known as MK-677, Nutrobal, ibutamoreno, GJ0EGN38UL, L 163191, L-163, 191, ibutamorenum, RefChem:55388, Ibutamoren [INN]

Effects Build muscle Sleep
Routes Oral
Legal status Research chemical
WADA Banned at all times

3D Molecular Structure of C27H36N4O5S

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  • Carbon
  • Hydrogen
  • Nitrogen
  • Oxygen
  • Sulfur

Chemistry

Formula
C27H36N4O5S
Molar mass
528.7
CAS
159634-47-6
PubChem CID
178024
IUPAC name
2-amino-2-methyl-N-[(2R)-1-(1-methylsulfonylspiro[2H-indole-3,4'-piperidine]-1'-yl)-1-oxo-3-phenylmethoxypropan-2-yl]propanamide
InChIKey
UMUPQWIGCOZEOY-JOCHJYFZSA-N

Reported dosing

User-reported

What has been reported in the literature and by users. This is a record of what is done, not a recommendation.

Typical dose 25 mg/day
Reported range 10-50 mg/day
Route Oral
Frequency Once daily
Duration 8-12 week course (unregulated use)

Also known as MK-677; never completed FDA approval (development for elderly frailty and cancer cachexia was discontinued after safety signals, including worsened insulin sensitivity and fluid retention). Not an approved drug.

Where this comes from Discontinued clinical trial data; user-reported/research-chemical vendor literature

There is no approved human dosing for this compound. The figures above are what users and vendors report, not what has been established as safe or effective. Treat them as a record of what is done, not as guidance.