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MK-677

Well Studied

Ghrelin Receptor Agonist | Oral Growth Hormone Secretagogue

Dose Start 12.5mg daily, increase to 25mg based on tolerance
Frequency Once daily, preferably at bedtime on empty stomach
Cycle 8-12 weeks for body composition goals
Storage Room temperature in cool, dry place; no refrigeration required

Oral compound activating ghrelin receptors to trigger growth hormone release while preserving natural production. Achieves superior oral bioavailability exceeding 60% with a 24-hour half-life, making it unique among GH secretagogues for its convenient once-daily oral dosing.

Mechanism of Action

Selectively binds GHS-R1a receptors in hypothalamus and pituitary, triggering pulsatile growth hormone release while maintaining natural circadian patterns.

Key Benefits

  • 97% increase in 24-hour growth hormone secretion
  • 40-72% elevation in IGF-1 levels
  • Enhanced sleep quality with improved REM patterns
  • Preferential lean tissue gains of 1.1-2.7kg over 8-12 months
  • 15% basal metabolic rate increase within 2 weeks
  • Oral administration (no injections required)
Molecular Weight
624.77 Da
Type
Non-peptide ghrelin receptor agonist

Growth Hormone

  • GH Restoration

    Restores youthful growth hormone levels in elderly subjects with 97% increase in 24-hour secretion.

  • IGF-1 Enhancement

    Sustained 40-72% IGF-1 elevation over extended periods.

  • Sleep Enhancement

    20% REM increase in younger adults; 50% improvement in elderly.

Body Composition

  • Muscle Preservation

    Demonstrates +2.69g/day nitrogen retention versus -8.97g/day placebo, protecting lean mass during caloric restriction.

  • Fat-Free Mass

    Increases fat-free mass with preferential lean tissue accrual.

  • Metabolic Rate

    15% basal metabolic rate elevation documented at 2 weeks.

Bone Health

  • Bone Formation

    39-45% increase in bone formation markers within 6-8 weeks.

Optimal bioavailability eliminates injection requirements with convenient daily dosing. Take at bedtime on empty stomach for best results.

GoalDoseFrequencyRoute
Body composition/anti-aging25mg1x dailyOral (bedtime, empty stomach)
Sleep quality improvement25mg1x nightlyOral (30 minutes before bed)
Conservative initiation12.5mg1x dailyOral (assess tolerance)
CJC-1295

Complementary GH pathways providing combined pulsatile and baseline elevation.

synergistic
Ipamorelin

Both stimulate GH release through different mechanisms.

synergistic
GHRP-2

MK-677 baseline elevation combines with GHRP-2 pulsatile spikes.

synergistic
TB-500

Non-competing mechanisms enhancing recovery effects.

compatible
BPC-157

Systemic growth factors complement localized healing.

compatible
HGH

Redundant effects without proportional benefits.

avoid
Insulin

MK-677 decreases insulin sensitivity; requires blood glucose monitoring.

monitor
LGD-4033

Case report documents 85.7% testosterone suppression and significant liver enzyme elevation when combined.

monitor
Week 1-2

Improved sleep quality, vivid dreams, possible appetite increase

Week 2-4

Enhanced recovery, better sleep architecture, initial body composition changes

Week 4-8

Noticeable lean mass gains, continued sleep benefits

Week 8-12

Maximum body composition improvements, sustained GH elevation

Common Side Effects

  • Appetite stimulation (>50% of users)
  • Water retention (30-40%)
  • Lethargy (20-30%)
  • Fasting glucose elevation (5-15mg/dL)

Stop Signs - Discontinue if:

  • Shortness of breath, chest pain, or unusual fatigue
  • Blood glucose levels >100mg/dL or diabetes symptoms
  • Liver enzyme elevation (ALT/AST >2x upper normal)
  • Severe fluid retention or unexplained swelling
  • Any concerning cardiovascular symptoms

Contraindications

  • Heart disease or congestive heart failure
  • Diabetes or pre-diabetes
  • Active cancer
  • Severe cardiovascular disease
  • Pregnancy or breastfeeding

Good Signs

  • Pharmaceutical-grade capsules with professional labeling
  • Batch numbers and expiration dates
  • Third-party testing documentation
  • Certificate of analysis showing >98% purity

Warning Signs

  • Products labeled 'for research only' may lack quality control

Bad Signs

  • Dietary supplement claims (FDA prohibits MK-677 in supplements)
  • Unknown purity or source without certificates of analysis
  • Unusually low prices suggesting counterfeit product
  • Growth Hormone Stimulation in Elderly
    (1996)

    25mg oral daily for 2 weeks showed 97% increase in 24-hour GH secretion in elderly adults.

  • Body Composition in Obese Subjects
    (1998)

    25mg oral daily for 2 months increased fat-free mass and energy expenditure in obese adults.

  • Reversal of Diet-Induced Catabolism
    (1998)

    25mg oral daily for 7 days showed nitrogen retention of +2.69g/day versus placebo -8.97g/day.

  • Sleep Quality Improvement Study
    (1997)

    25mg oral daily for 1 week showed 20% REM increase in young adults; 50% in elderly.

  • Bone Turnover Markers Study
    (1999)

    25mg oral daily for 2 months showed 39-45% increase in bone formation markers in elderly adults.

Disclaimer

This information is for educational and research purposes only. Consult a healthcare professional before use.