Compare Peptides
Select any two compounds for a side-by-side comparison of mechanism, uses, risks, and FDA regulatory status.
Popular comparisons
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.
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.
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.
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.
- Skin tanning
- Sexual dysfunction treatment
- Libido enhancement
- Erectile dysfunction (investigational)
- Female sexual dysfunction (FDA-approved indication)
- Male sexual dysfunction (off-label)
- Libido enhancement
- Erectile dysfunction (off-label)
- 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
- Nausea (most common side effect — ~40% in trials)
- Flushing
- Headache
- Transient blood pressure increase
- Hyperpigmentation with repeated use
- Injection site reactions
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
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.
This comparison is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting any peptide therapy.