Comparison

IGF-1 LR3 vs MK-677

Side-by-side attributes from our library comparison data. Read each peptide leaf for dosing math, regulatory status, and citations.

IGF-1 LR3 vs. MK-677

AttributeIGF-1 LR3MK-677
AdministrationSubcutaneous injectionOral (daily)
MechanismDirect IGF-1 receptor agonistGhrelin receptor agonist → GH → IGF-1
IGF-1 ElevationDirect, immediate, strongIndirect - GH stimulation cascade
Half-Life20–30 hours (LR3 modification)24-hour sustained oral action
Muscle UptakeDirect muscle anabolic signalingSystemic GH/IGF-1 elevation
WADA StatusProhibited (S2)Prohibited (S2)

Verdict: IGF-1 LR3 offers direct, potent anabolic signaling at the receptor level - typically stronger for muscle hypertrophy than MK-677. However, MK-677 also provides GH itself (bone density, sleep, recovery) via the indirect GH cascade.