Growth hormone & performance
MK-677 (Ibutamoren)
A growth-hormone secretagogue (ibutamoren) tested in human trials.
Not a peptide. Included because it is part of the catalog.
How it works
It activates the ghrelin receptor like the GHRPs, but it is not a peptide. One dose raises GH and IGF-1 for about a day.
What it is used for
Studied for muscle loss in older adults, recovery after hip fracture, GH deficiency and sleep.
What the evidence says
Trials of up to two years raised IGF-1 and lean mass without clear gains in strength or function. A hip-fracture trial was stopped early because of more heart-failure cases.
Side effects and cautions
More appetite, water retention, higher blood sugar and insulin resistance, and a possible heart-failure risk in vulnerable people.
Half-life
About 4–6 hours (clinical studies)
Makes sense for
- Older adults with muscle loss, within research
Does not make sense for
- Diabetes or prediabetes
- Heart failure
- People who retain water easily
Boost the effect
- Limit sugar and refined carbs: it raises blood sugar
- Strength training: helps turn the extra growth hormone into lean mass