MK-677 (Ibutamoren)
The only oral growth hormone secretagogue. MK-677 elevates GH and IGF-1 through ghrelin receptor activation — improving deep sleep, body composition, and recovery without injections.
MK-677 (ibutamoren) mimics ghrelin to stimulate pulsatile GH release from your pituitary. Unlike injectable peptides, you take it as a daily pill. A 2-year RCT in elderly adults showed it restored GH and IGF-1 to young-adult levels, improved sleep quality, and increased fat-free mass. The trade-offs: hunger and potential blood sugar effects.
Who's interested: People wanting GH elevation without injections, those prioritising deep sleep improvement, and anyone seeking convenient long-term GH support.
Dive deeper into the researchPotential side effects
- Significant appetite increase, especially weeks 1–6
- Mild water retention (1–3 kg)
- Potential fasting glucose elevation — monitor HbA1c
What does MK-677 do?
MK-677 mimics ghrelin — your hunger hormone — by binding to the same receptor (GHS-R1a) in your hypothalamus and pituitary. This triggers pulsatile GH release that preserves your body's natural feedback, unlike exogenous GH injections which deliver flat doses.
The key advantage: it's orally bioavailable with a ~24-hour half-life, allowing once-daily dosing. This makes it far more convenient than injectable GH secretagogues like ipamorelin or GHRP-2 that require multiple daily shots.
Who uses it?
- Sleep improvement — one of the most consistent benefits; ~50% increase in slow-wave (deep) sleep
- Body composition — increased lean mass and reduced visceral fat over 6–12 months
- Recovery — accelerated wound healing and connective tissue repair via elevated GH/IGF-1
- Anti-aging — restoring youthful GH/IGF-1 levels without injections
- Bone density — 12-month+ use shows improved BMD markers
What to know before trying
Always take MK-677 at bedtime. This maximises synergy with your natural GH pulses during deep sleep and reduces daytime appetite impact.
- Start low — 10 mg for sleep and recovery; go to 25 mg only if tolerated and needed
- Hunger is real — the appetite increase from ghrelin receptor activation is the main complaint
- Watch blood sugar — MK-677 can elevate fasting glucose and reduce insulin sensitivity, especially at 25 mg
- Cycle or run continuously? — both approaches are used; 8–12 weeks on / 4 weeks off may preserve receptor sensitivity
- Not a SARM — sometimes misclassified with SARMs, but MK-677 has no androgenic activity
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Get early accessFrequently Asked Questions
Is MK-677 a steroid or a peptide?
Neither. MK-677 is a non-peptide ghrelin receptor agonist (growth hormone secretagogue). Unlike injectable peptides, it is orally active. Unlike steroids, it has no androgenic or anabolic hormonal effects — it simply stimulates your pituitary to release more growth hormone.
How much does MK-677 increase growth hormone?
Clinical studies show MK-677 at 25 mg/day increases GH secretion by 40–80% and IGF-1 levels by 40–60% within 2–4 weeks. Effects on pulsatile GH release closely mimic natural patterns.
Does MK-677 cause water retention and hunger?
Yes. Appetite increase occurs in most users, especially in the first 4–8 weeks, from ghrelin receptor activation. Mild water retention (1–3 kg) is common due to elevated GH. Both effects typically moderate over time but do not fully resolve.
Is MK-677 legal and available in India?
MK-677 is not approved as a pharmaceutical in India. It is sold as a research chemical through online vendors. It is not a scheduled substance under NDPS but falls in a regulatory grey area. Quality varies — always demand third-party HPLC testing.
How it works in your body
- Ghrelin mimicry — binds GHS-R1a with high affinity, triggering GH release
- Pulsatile GH — preserves natural pulsatile pattern, unlike exogenous GH
- IGF-1 elevation — sustained 40–60% increase reflects ongoing GH activity
- Deep sleep enhancement — increases Stage 3 and REM sleep by ~50%
- 24-hour half-life — convenient once-daily dosing
Clinical evidence
- 2-year elderly RCT (Nass 2008): 25 mg/day increased GH and IGF-1 to young-adult levels, improved fat-free mass, enhanced sleep without serious adverse events
- Sleep study: 50% increase in slow-wave sleep duration
- Bone density: Improved BMD markers over 12 months in postmenopausal women
- Nitrogen balance: Anti-catabolic during caloric restriction
Side effects & safety
- Appetite increase — the most common complaint; ghrelin-driven, most pronounced weeks 1–6
- Water retention — mild (1–3 kg), stabilises after 4–6 weeks
- Fasting glucose elevation — can reduce insulin sensitivity; monitor HbA1c every 3 months
- Lethargy — vivid dreams and morning grogginess at 25 mg
- Prolactin — mild transient elevation; clinically insignificant at standard doses
Avoid if you have active cancer (IGF-1 is a growth factor), uncontrolled diabetes or insulin resistance, or pituitary tumors.
Which labs to monitor
- IGF-1 — primary efficacy marker
- Fasting glucose & HbA1c — every 3 months during use
- Prolactin — baseline and follow-up
- Sleep tracking — wearable data for deep sleep changes
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