IGF-1 LR3 vs MK-677
limited vs Well Studied
monitor Researched · 90% May compound metabolic effects through GH stimulation.
Molecular Data
IGF-1 LR3 MK-677
Weight — 624.77 Da
Half-life 20-30 hours ~24 hours
Chain 83 amino acids —
Type Synthetic IGF-1 analog Non-peptide ghrelin receptor agonist
Key Benefits
IGF-1 LR3
01 Approximately 3x more potent than native IGF-1
02 Promotes muscle hypertrophy and hyperplasia in animal models
03 15-20% lean mass gains observed in 4-week rat studies
04 Anti-catabolic effects preserve muscle during cachexia
05 20-30 hour half-life for sustained effects
MK-677
01 97% increase in 24-hour growth hormone secretion
02 40-72% elevation in IGF-1 levels
03 Enhanced sleep quality with improved REM patterns
04 Preferential lean tissue gains of 1.1-2.7kg over 8-12 months
05 15% basal metabolic rate increase within 2 weeks
06 Oral administration (no injections required)
Dosing Protocols
IGF-1 LR3
20-100 mcg daily (start low at 20-30 mcg) / Once daily, or split AM/PM for higher doses
Beginner Protocol 20-30mcg Once daily post-workout
Intermediate 40-60mcg Once daily
Advanced 80-100mcg Once or split AM/PM
Women's Protocol 10-20mcg Once daily
MK-677
Start 12.5mg daily, increase to 25mg based on tolerance / Once daily, preferably at bedtime on empty stomach
Side Effects
IGF-1 LR3
Hypoglycemia (lasting up to 30 hours) - CRITICAL
Water retention
Joint stiffness
Muscle soreness
Increased pump during workouts
MK-677
Appetite stimulation (>50% of users)
Water retention (30-40%)
Lethargy (20-30%)
Fasting glucose elevation (5-15mg/dL)
Note on testosterone suppression: at doses up to 20 mg daily, MK-677 is unlikely to cause significant testosterone suppression on its own. Above 20 mg daily, the likelihood of suppression and other side effects (insulin resistance, water retention, lethargy) increases. The case report documenting 85.7% testosterone suppression involved co-administration with LGD-4033, a SARM known to be profoundly suppressive, making the SARM the likely primary driver of that suppression.
Contraindications
NEVER approved for human use - research chemical only
Cancer history or undiagnosed growths
May cause organ hypertrophy (heart, intestines)
WADA prohibited - causes failed drug tests
Heart disease or congestive heart failure
Diabetes or pre-diabetes
Active cancer
Severe cardiovascular disease
Pregnancy or breastfeeding
Research Evidence
IGF-1 LR3 MK-677
Status limited Well Studied
References 4 studies 7 studies
Latest November 2024 July 2024
FDA Approved No No
This comparison is for educational and research purposes only. Consult a healthcare professional before use.