- For in vitro testing and laboratory use only.
- Not for human or animal consumption.
- Bodily introduction is illegal.
- Handle only by licensed professionals.
- Not a drug, food, or cosmetic.
- Educational use only.
This guide covers practical dosing ranges for IGF-1 LR3, the long-arginine analog of IGF-1 with an extended half-life of roughly 20–30 hours and significantly higher systemic activity than native IGF-1. It is written for recreational physique athletes, researchers, and recovery-focused users who want a clear picture of how the compound is actually run. Numbers below draw on preclinical data, the original Cephalon/Insmed clinical work on rhIGF-1, and community protocols refined over two decades of bodybuilding use.
Dosing by Experience Level
| Experience Level | Dose | Frequency | Notes |
|---|---|---|---|
| Beginner | 20–30 mcg | Once daily | Assess hypoglycemia response before scaling |
| Standard | 40–60 mcg | Once daily | Inject post-workout on training days |
| Intermediate | 60–80 mcg | Once daily | Consider bilateral site injections near worked muscles |
| Aggressive | 80–120 mcg | Once daily | Gut distension and numbness risk rises sharply |
| Clinical (Increlex) | 0.04–0.12 mg/kg | Twice daily | FDA-approved only for pediatric severe primary IGF-1 deficiency |
Doses also shift depending on the specific goal. IGF-1 LR3 used for localized hypertrophy follows a different logic than systemic recomposition or recovery protocols.
Dosing by Goal
| Goal | Recommended Dose | Frequency | Cycle Length |
|---|---|---|---|
| Lean muscle gain | 40–60 mcg | Once daily | 4–6 weeks |
| Site-specific hypertrophy | 20–40 mcg per site | Post-workout, training days only | 4 weeks |
| Recovery between heavy blocks | 30–50 mcg | Once daily | 3–4 weeks |
| Nutrient partitioning during bulk | 50–80 mcg | Once daily, pre-meal | 4–6 weeks |
| Stacked with anabolics | 40–50 mcg | Once daily | 4 weeks, then 4 weeks off |
Practical Notes
Start at the beginner dose regardless of experience with GH or other peptides — IGF-1 LR3 has a steep response curve, and hypoglycemia, headaches, and numbness in the extremities tend to show up within the first few injections at higher doses. Avoid running cycles longer than 6 weeks continuously; receptor downregulation is real, and extended exposure raises legitimate concerns about accelerated growth of any pre-existing abnormal tissue. Anyone with a personal or family history of cancer, active tumors, or diabetic retinopathy should not use this compound without direct oncology or endocrinology oversight.
