MK-677 (Ibutamoren)
Orally active ghrelin receptor agonist (not a peptide). Boosts growth hormone and IGF-1. Known for improving deep sleep, increasing appetite, and gradually improving body composition.
Key Facts
- ClassificationIbutamoren (MK-677) is an orally active non-peptide GHS mimicking ghrelin at GHSR-1a.
- Primary BenefitsSleep (8/10) · Muscle Growth (7/10) · Fat Loss (5/10)
- AdministrationOral
- Typical Dose10-25 mg by mouth daily, ideally before bed. Can be used long-term, but keep an eye on bloodwork.
- Evidence StrengthModerate — 20 peer-reviewed studies referenced · Community sentiment 6/10
- Stacks Well WithCJC-1295 with DAC, Ipamorelin, Sermorelin, DSIP
- Legal StatusResearch Use Only · not prescribable in US · WADA prohibited
Quick Facts
- From price
- $45
- Type
- capsule
- Administration
- Oral
- Evidence
- moderate
- Studies referenced
- 20
- Community sentiment
- 6/10
- Stacks with
- 5 peptides
- Regulatory
- Research Use Only
Top benefits
Week 1–2
Significant appetite increase within days. Improved sleep quality (deeper, more vivid dreams). Mild water retention and bloating. Lethargy possible.
Week 3–6
Enhanced recovery from training. Fat loss may begin despite appetite increase. Skin and hair improvements. Increased muscle fullness. Elevated IGF-1 on labs.
Week 8+
Substantial body recomposition. Bone density improvements. Sustained sleep quality. Hair growth. Some users note joint pain relief from increased GH.
Common Side Effects
Scientific Overview
Ibutamoren (MK-677) is an orally active non-peptide GHS mimicking ghrelin at GHSR-1a. Produces sustained 24-hour GH elevation and 40-60% IGF-1 increase. Clinical trials in elderly showed improved lean mass, bone density, and sleep architecture. Preserves pulsatile GH secretion. Side effects include appetite stimulation and transient insulin resistance.
Dosing
10-25 mg by mouth daily, ideally before bed. Can be used long-term, but keep an eye on bloodwork.
Reconstitution, storage, injection sites & timing
Benefit Profile
| Vendor | Variant | Price | |
|---|---|---|---|
| Limitless Biotech | 30ct 25mg | $54.99 | Code: PSTACK10Buy |
| Skye Peptides | 30ct 10mg | $49.99 | |
| Skye Peptides | 30ct 25mg | $69.99 | |
| Swiss Chems ⚠ FDA warning letter received late 2024 | 60ct 10mg | $69.95 | |
| Amino Asylum ⚠ Reported federal raid in 2025 | 30ct 25mg | $44.99BEST |
Stacks Well With
CJC-1295 with DAC
Long-lasting growth hormone booster. The DAC modification keeps it active for days, producing steady GH elevation for muscle growth, fat loss, and recovery.
Ipamorelin
One of the cleanest GH boosters. Stimulates growth hormone release without affecting cortisol or prolactin, meaning fewer side effects than other GH peptides.
Sermorelin
One of the most prescribed GH peptides. Copies the first 29 amino acids of natural GHRH, triggering physiological GH pulses from the pituitary.
DSIP (Delta Sleep-Inducing Peptide)
Brain peptide that promotes deep delta-wave sleep. Normalizes disrupted sleep patterns and reduces stress without next-day grogginess.
Epithalon (Epitalon)
Longevity peptide from the pineal gland. Activates telomerase to protect DNA caps and restores melatonin production. Russian studies showed 11-16% lifespan increase in animals.
Compare
MK-677 (Ibutamoren) and CJC-1295 both elevate growth hormone levels, but through entirely different mechanisms and routes. MK-677 is technically not a peptide -- it's a non-peptide ghrelin mimetic taken orally. CJC-1295 is a GHRH analog that requires injection. This distinction significantly affects their use profiles.
Ipamorelin vs MK-677Ipamorelin and MK-677 both stimulate growth hormone release through ghrelin-related pathways, but with important differences in selectivity and side effect profiles. Ipamorelin is a true peptide requiring injection, while MK-677 is a non-peptide small molecule taken orally.