IGF-1 LR3 vs PT-141
Head-to-head comparison of IGF-1 LR3 (Insulin-like Growth Factor-1 Long R3) and PT-141 (Bremelanotide (Melanocortin Receptor Agonist)) — benefits, dosing, side effects, research data, and where to buy.
| Property | IGF-1 LR3 | PT-141 |
|---|---|---|
| Category | Performance | Performance |
| Full Name | Insulin-like Growth Factor-1 Long R3 | Bremelanotide (Melanocortin Receptor Agonist) |
| Molecular Weight | 9,117 Da | 1,025.2 Da |
| Half-Life | ~20-30 hours | ~2.7 hours |
| Amino Acids | 83 | 7 |
| Typical Dose | 20-100 mcg | 1.75 mg |
| Route | IM / SC | SC |
| Purity | — | — |
| Studies Count | 298 | 178 |
| Research Status | Pre-clinical | FDA Approved |
IGF-1 LR3 Benefits
- ✓Promotes muscle hyperplasia (new muscle cells)
- ✓Extended half-life vs native IGF-1
- ✓Enhanced protein synthesis
- ✓Improved nutrient partitioning
- ✓Anti-catabolic effects
PT-141 Benefits
- ✓Enhances sexual desire and arousal
- ✓Works through CNS (not vascular)
- ✓FDA-approved for HSDD
- ✓Effective for both men and women
- ✓Does not require sexual stimulation to work
IGF-1 LR3 Dosing
Standard: 20-50 mcg IM post-workout|Advanced: 50-100 mcg IM or SC daily|Cycle: 4-6 weeks on, 4 weeks off
PT-141 Dosing
Standard: 1.75 mg SC, 45 min before activity|Max frequency: Once every 24 hours|Max: 8 doses per month|Men (off-label): 1-2 mg SC as needed
IGF-1 LR3 Side Effects
- ⚠Common: Hypoglycemia (dose-dependent), joint pain, water retention
- ⚠Moderate: Gut growth concern (high doses), acromegaly-like symptoms
- ⚠Serious: Theoretical cancer risk (prolonged high-dose use)
PT-141 Side Effects
- ⚠Common: Nausea (40%), flushing, headache, injection site reactions
- ⚠Moderate: Elevated blood pressure (transient), fatigue
- ⚠Serious: Focal hyperpigmentation with repeated use
- ⚠Contraindications: Uncontrolled hypertension, cardiovascular disease
Research Overview
IGF-1 LR3
IGF-1 LR3 has extensive in vitro and animal data. Its role in muscle hyperplasia is well-documented. The extended half-life modification provides practical advantages over native IGF-1.
PT-141
PT-141 has robust clinical evidence including multiple Phase III trials. FDA-approved in 2019. Unique mechanism of action through melanocortin-4 receptors in the brain. Well-characterized safety and efficacy profile.
Ready to buy?
Find both peptides from our verified, lab-tested vendors with purity certificates and third-party testing.