IGF-1 LR3 vs PT-141 (Bremelanotide)
Side-by-side comparison of key properties, dosing, and research.
Anabolic & IGF
IGF-1 LR3Sexual Health & Libido
PT-141 (Bremelanotide)- Summary
- IGF-1 LR3 is a synthetic analog of Insulin-like Growth Factor-1 with an extended half-life. It is one of the most potent anabolic peptides available, directly stimulating muscle cell hyperplasia and hypertrophy, and is the downstream mediator of many of GH's anabolic effects.
- PT-141 (Bremelanotide) is a cyclic peptide melanocortin receptor agonist that enhances sexual desire and arousal through central nervous system mechanisms. It is FDA-approved as Vyleesi for premenopausal women with hypoactive sexual desire disorder (HSDD).
- Half-Life
- 20–30 hours
- 2–3 hours
- Admin Route
- SubQ, IM
- SubQ
- Research
- —
- —
- Typical Dose
- 40–80 mcg
- 0.5–1.75 mg
- Frequency
- Once daily or split twice daily
- As needed (not daily)
- Key Benefits
- Direct muscle hypertrophy via IGF-1R stimulation
- Muscle hyperplasia (new fiber formation) — unique among peptides
- Rapid gains in lean muscle mass
- Accelerated recovery from training and injury
- Increased nutrient uptake by muscle cells
- Fat oxidation enhancement
- Bone density improvement
- Cartilage and connective tissue repair
- Enhances sexual desire and libido in both men and women
- Improves arousal through central nervous system activation
- Effective for psychological erectile dysfunction
- Works for female sexual arousal disorder
- May improve sexual satisfaction and intensity
- Fast-acting — effects within 45–60 minutes
- FDA-approved for HSDD in premenopausal women
- Side Effects
- Hypoglycemia (significant risk — insulin-like activity)
- Acromegaly-like effects with excessive long-term use
- Jaw and hand swelling
- Organ hypertrophy with extreme doses
- +2 more
- Nausea (most common — 40% of users in clinical trials)
- Facial flushing and warmth
- Transient blood pressure changes (typically increase then normalize)
- Headache
- +2 more
- Stacks With
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