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MK-677 (Ibutamoren)

Research Use Only
capsuleOral

An oral pill that tells your body to release more growth hormone and IGF-1 (a key growth signal). It's well-known for improving deep sleep, increasing appetite, and gradually building muscle while burning fat over time.

What to Expect

1

Week 1–2

Significant appetite increase within days. Improved sleep quality (deeper, more vivid dreams). Mild water retention and bloating. Lethargy possible.

2

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.

3

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

Increased appetite (very common)Water retention/bloatingLethargyNumbness/tingling in handsElevated fasting blood glucoseVivid dreams
Tolerance: Moderate — appetite stimulation often diminishes but GH effects persist. Some desensitization after 6-12 months
Cycling: 8-12 weeks on, 4-8 weeks off. Monitor fasting glucose and HbA1c. Some run 5 days on / 2 off to manage appetite.

Scientific Overview

Ibutamoren (MK-677) is an orally active, non-peptide growth hormone secretagogue mimicking ghrelin's action at the GHSR-1a receptor. It produces sustained 24-hour GH elevation and increases IGF-1 levels by 40–60% over baseline. Clinical trials in elderly subjects demonstrated improved lean body mass, bone mineral density, and sleep architecture (increased REM and Stage IV duration). Unlike exogenous GH, MK-677 preserves normal pulsatile GH secretion patterns. Notable side effects include appetite stimulation via hypothalamic ghrelin pathways 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.

Practical Guide

Storage

Store capsules/liquid at room temperature away from moisture and light. No reconstitution needed — oral compound.

Timing

Take before bed to align with natural GH pulse and sleep through appetite increase. Some take in the morning if appetite stimulation is desired.

Food

Can be taken with or without food. Taking with food may reduce nausea. Some users prefer empty stomach for maximum GH pulse.

Benefit Profile

😴 Sleep
8/10
💪 Muscle Growth
7/10
🔥 Fat Loss
5/10
Longevity
4/10
Skin & Hair
4/10
🩹 Injury Healing
4/10

Medical Considerations

Medical oversight strongly recommendedNot safe during pregnancy

Contraindications

  • Diabetes or pre-diabetes (raises fasting glucose)
  • Active cancer
  • Pituitary tumors
  • Pregnancy/nursing
  • Congestive heart failure (water retention)

Drug Interactions

Insulin and oral hypoglycemics (GH-mediated insulin resistance)GlucocorticoidsCYP3A4 inhibitors (ketoconazole, itraconazole)

Recommended Monitoring

  • Fasting glucose and HbA1c every 3 months
  • IGF-1 levels every 3 months
  • Monitor for edema
  • Fasting insulin levels

This information is for educational purposes only. Always consult a qualified healthcare provider before starting any peptide protocol.

Pricing

VendorVariantPrice
Limitless Biotech30ct 25mg$54.99
Code: PSTACK10Buy
Skye Peptides30ct 10mg$49.99
Skye Peptides30ct 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

Published Research

20 studies indexed(1996–2025)16 clinical trials4 reviews

Oral ghrelin receptor agonist MK-0677 increases serum insulin-like growth factor 1 in hemodialysis patients: a randomized blinded study.

Campbell GA, Patrie JT, et al.·Nephrol Dial Transplant·2018
Clinical Trial

MK-0677 (ibutamoren mesylate) for the treatment of patients recovering from hip fracture: a multicenter, randomized, placebo-controlled phase IIb study.

Adunsky A, Chandler J, et al.·Arch Gerontol Geriatr·2011
Clinical Trial

Growth hormone secretagogue MK-677: no clinical effect on AD progression in a randomized trial.

Sevigny JJ, Ryan JM, et al.·Neurology·2008
Clinical Trial

The effect of treatment with the oral growth hormone (GH) secretagogue MK-677 on GH isoforms.

Svensson J, Boguszewski CL, et al.·Growth Horm IGF Res·2003
Clinical Trial

Effects of oral administration of ibutamoren mesylate, a nonpeptide growth hormone secretagogue, on the growth hormone-insulin-like growth factor I axis in growth hormone-deficient children.

Codner E, Cassorla F, et al.·Clin Pharmacol Ther·2001
Clinical Trial

Effect of alendronate and MK-677 (a growth hormone secretagogue), individually and in combination, on markers of bone turnover and bone mineral density in postmenopausal osteoporotic women.

Murphy MG, Weiss S, et al.·J Clin Endocrinol Metab·2001
Clinical Trial

Oral administration of the growth hormone secretagogue MK-677 increases markers of bone turnover in healthy and functionally impaired elderly adults. The MK-677 Study Group.

Murphy MG, Bach MA, et al.·J Bone Miner Res·1999
Clinical Trial

Discrepancy between serum leptin values and total body fat in response to the oral growth hormone secretagogue MK-677.

Svensson J, Carlsson B, et al.·Clin Endocrinol (Oxf)·1999
Clinical Trial

Treatment of obese subjects with the oral growth hormone secretagogue MK-677 affects serum concentrations of several lipoproteins, but not lipoprotein(a).

Svensson J, Jansson JO, et al.·J Clin Endocrinol Metab·1999
Clinical Trial

MK-677, an orally active growth hormone secretagogue, reverses diet-induced catabolism.

Murphy MG, Plunkett LM, et al.·J Clin Endocrinol Metab·1998
Clinical Trial
Showing 10 of 20 studies. Search PubMed for the complete list.