PEG-MGF vs PT-141 (Bremelanotide)
A detailed comparison to help you understand the differences and choose the right peptide for your research goals.
PEG-MGF
PEG-MGF (PEGylated Mechano Growth Factor) is a variant of IGF-1 that is produced in response to muscle damage. PEGylation extends its half-life from minutes to several hours, making it practical for use.
Full details →PT-141 (Bremelanotide)
PT-141, also known as Bremelanotide, is a synthetic peptide analog of alpha-melanocyte-stimulating hormone. It is the only FDA-approved treatment for hypoactive sexual desire disorder (HSDD) in premenopausal women.
Full details →Side-by-Side Comparison
| Aspect | PEG-MGF | PT-141 (Bremelanotide) |
|---|---|---|
| Mechanism | Activates muscle satellite cells (stem cells) and promotes their fusion to existing muscle fibers for repair and growth. MGF is produced naturally in response to mechanical stress on muscles. | PT-141 activates melanocortin receptors (MC3R and MC4R) in the central nervous system, particularly in areas associated with sexual arousal. Unlike PDE5 inhibitors, it works through the nervous system rather than the vascular system. |
| Typical Dosage | Research protocols typically use 200-400mcg injected into targeted muscle groups 2-3 times weekly, usually post-workout. | FDA-approved dose: 1.75mg administered subcutaneously at least 45 minutes before anticipated sexual activity. Not to be used more than once within 24 hours or more than 8 times per month. |
| Administration | Intramuscular injection, ideally into muscles trained that day. Best administered post-workout when satellite cell activation is relevant. | Subcutaneous injection in the abdomen. Available as Vyleesi (commercial product). Research use may involve different dosing protocols. |
| Side Effects | Injection site soreness, potential hypoglycemia, and localized swelling. Generally well-tolerated. | Common side effects include nausea (40% of users), flushing, headache, and injection site reactions. Transient blood pressure increases may occur. |
| Best For |
What They Have in Common
Both PEG-MGF and PT-141 (Bremelanotide) are commonly used for: