How does MK-677 affect sleep architecture and REM sleep?

Clinical research published in PubMed shows that MK-677 (ibutamoren) at 25mg taken at bedtime increased REM sleep by 20% in young subjects and up to 50% in older adults, while also increasing slow-wave deep sleep by approximately 50% in younger individuals. The compound works by stimulating growth hormone release through ghrelin receptor activation, which naturally occurs during sleep. Study participants also experienced reduced sleep deviations and shorter REM latency, though MK-677 remains an investigational compound without FDA approval.