MK-677 (Ibutamoren) vs SLU-PP-332
Side-by-side comparison of key properties, dosing, and research.
Growth Hormone Peptides
MK-677 (Ibutamoren)Recovery & RepairFat Loss & Metabolic
SLU-PP-332- Summary
- MK-677 (Ibutamoren) is an orally active, non-peptide ghrelin receptor agonist that increases growth hormone and IGF-1 levels. Unlike injectable GHRPs, it can be taken orally and has a 24-hour half-life, making it convenient for sustained GH optimization.
- SLU-PP-332 is a small molecule exercise mimetic that activates estrogen-related receptors ERRalpha and ERRdelta (ERRa/d), transcription factors that drive oxidative metabolism programs. In animal studies it significantly enhanced endurance capacity and metabolic fitness without exercise, mimicking many of the cardiovascular and metabolic adaptations of aerobic training.
- Half-Life
- 24 hours
- Not established in humans; rodent pharmacokinetics suggest hours
- Admin Route
- Oral
- Oral (research), Subcutaneous (research)
- Research
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- Typical Dose
- 10–25 mg
- Not established for humans; rodent studies used ~100 mg/kg/day
- Frequency
- Once daily
- Once daily in rodent studies
- Key Benefits
- Increases lean muscle mass
- Enhances bone density
- Improves sleep quality and REM sleep
- Accelerates recovery from training
- Increases appetite
- May improve skin elasticity and appearance
- Supports fat loss while maintaining muscle
- Oral administration — no injections required
- 24-hour half-life allows once-daily dosing
- Significant enhancement of aerobic endurance capacity
- Increases mitochondrial density and oxidative metabolism in muscle
- Promotes beneficial shift toward oxidative muscle fiber phenotype
- Improves cardiac efficiency and cardiovascular fitness markers
- Potential for obesity, metabolic syndrome, and heart failure treatment
- Exercise mimetic for populations unable to exercise (disability, frailty, disease)
- Side Effects
- Increased appetite (significant in some users)
- Water retention and puffiness
- Elevated blood glucose / insulin resistance (monitor in diabetics)
- Lethargy initially
- +2 more
- Limited human data; all studies are preclinical (rodent)
- Unknown cardiovascular effects with long-term or high-dose use in humans
- Potential hormonal interactions via ERR pathway (ERRs modulate estrogen-related signaling)
- Off-target effects not fully characterized
- Stacks With
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