Compare Peptides
Select any two compounds for a side-by-side comparison of mechanism, uses, risks, and FDA regulatory status.
Popular comparisons
A synthetic melanocortin receptor agonist derived from Melanotan II. Unlike Melanotan II, PT-141 was developed specifically for sexual dysfunction and received FDA approval in 2019 as Vyleesi for hypoactive sexual desire disorder (HSDD) in premenopausal women.
A synthetic analog of alpha-MSH that acts on melanocortin receptors. Originally developed at the University of Arizona as a potential tanning agent, it gained notoriety for potent sexual arousal and appetite suppression effects.
Activates melanocortin receptors (MC3R and MC4R) in the central nervous system, increasing sexual desire through a brain-based mechanism rather than vascular effects. This distinguishes it from PDE5 inhibitors like sildenafil which work peripherally.
Activates MC1R (melanocortin 1 receptor) to stimulate melanin production. Also activates MC3R and MC4R, which mediate sexual arousal, appetite suppression, and cardiovascular effects. The MC4R activation is primarily responsible for its erectile and libido-enhancing properties.
- Female sexual dysfunction (FDA-approved indication)
- Male sexual dysfunction (off-label)
- Libido enhancement
- Erectile dysfunction (off-label)
- Skin tanning
- Sexual dysfunction treatment
- Libido enhancement
- Erectile dysfunction (investigational)
- Nausea (most common side effect — ~40% in trials)
- Flushing
- Headache
- Transient blood pressure increase
- Hyperpigmentation with repeated use
- Injection site reactions
- Nausea and vomiting (common)
- Facial flushing
- Spontaneous and prolonged erections
- Melanocyte stimulation may activate existing moles or nevi
- Potential cardiovascular effects
- High abuse potential from gray market
- Very limited controlled clinical trial data
FDA-approved as Vyleesi (bremelanotide injection) in June 2019 for hypoactive sexual desire disorder (HSDD) in premenopausal women. Off-label use for male sexual dysfunction is common through telehealth clinics. Available through compounding pharmacies with prescription.
Removed from FDA 503A Category 2 effective April 22, 2026. Scheduled for PCAC review before February 2027. One of the more controversial compounds on the list due to its widespread gray-market use and safety concerns. Compounding not yet authorized — status is in regulatory gray zone pending PCAC recommendation.
PCAC: By February 2027
This comparison is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting any peptide therapy.