PT-141 (Bremelanotide) is one of the most extensively investigated research peptides in sexual function and arousal research.

Originally developed from the melanocortin peptide Melanotan II, PT-141 was designed to selectively investigate melanocortin pathways involved in sexual motivation while minimising the pigmentation effects associated with earlier melanocortin analogues.

Unlike compounds such as sildenafil or tadalafil, PT-141 does not primarily investigate blood flow or vascular function. Instead, published research focuses on central nervous system pathways regulating sexual desire, motivation and arousal, making PT-141 one of the most distinctive peptides in sexual medicine research.

Why PT-141 is widely investigated

PT-141 has become a key research peptide because it targets central melanocortin signalling, a pathway that differs fundamentally from vascular approaches to sexual function.

Published studies have investigated PT-141 in relation to:

sexual desire
sexual arousal
female sexual function
male sexual function
melanocortin receptor biology
central nervous system signalling
neuroendocrine regulation

Because these pathways originate within the brain rather than the vascular system, PT-141 has attracted significant attention in neuroscience and sexual medicine research.

How PT-141 works

Unlike PDE-5 inhibitors, PT-141 is primarily investigated for its effects on melanocortin receptors, particularly MC4R and, to a lesser extent, MC3R.

Published research has explored its relationship with:

Melanocortin signalling

Activation of melanocortin pathways involved in sexual motivation and behavioural responses.

Central arousal pathways

Investigation of hypothalamic circuits associated with sexual desire and arousal.

Dopaminergic signalling

Research suggests melanocortin activation influences downstream neurochemical pathways involved in motivation and reward.

Neuroendocrine regulation

Experimental work has examined how PT-141 interacts with central nervous system networks involved in sexual behaviour.

Why PT-141 is widely investigated in sexual medicine

PT-141 differs from many compounds investigated in sexual medicine because its primary mechanism is central rather than peripheral.

Published clinical research has investigated:

hypoactive sexual desire disorder (HSDD)
female sexual arousal
male erectile function
sexual motivation
central melanocortin signalling

This distinction has made PT-141 an important research tool for studying the neurobiology of sexual function rather than vascular physiology alone.

Human and preclinical research

Compared with many research peptides, PT-141 has a substantial clinical evidence base.

Multiple Phase II and Phase III studies have investigated Bremelanotide in women with hypoactive sexual desire disorder, while earlier clinical programmes explored its effects in men with erectile dysfunction. Together, these studies established PT-141 as one of the most clinically investigated peptides targeting melanocortin pathways.

Why PT-141 differs from Viagra® and Cialis®

One of PT-141’s defining characteristics is that it investigates central sexual desire pathways rather than vascular physiology.

PT-141	PDE-5 inhibitors
Melanocortin signalling	Nitric oxide pathway
Sexual desire research	Erectile physiology
Central nervous system	Peripheral blood flow
Investigated in both men and women	Primarily investigated in male erectile function

Because these mechanisms differ, PT-141 represents an entirely different area of sexual medicine research rather than another vascular approach.

Published safety observations

Across published clinical studies, the most commonly reported adverse events included nausea, flushing and headache, particularly during early administration. Most events were described as mild to moderate in severity, although tolerability varied between studies and populations, and tend to dissappear completely with repeated use.

Product characteristics

Application: laboratory and analytical research
Use restriction: not for human consumption; not for medical, veterinary or cosmetic use
Produced in GMP-compliant facilities under strict QC protocols.
Each batch carefully lab tested after production (you can find Certificate of Analysis under product pictures).
Freeze-dried (lyophilized) for maximum stability and extended shelf life.
Sealed in sterile vials, ready for reconstitution.
Purity: ≥99% (HPLC-tested)
Appearance: Lyophilized white/off-white powder
Molecular formula: C₅₀H₆₈N₁₄O₁₀
Molecular weight: 1025.2
Sequence: Ac-Nle-Asp-His-D-Phe-Arg-Trp-Lys-OH ChemicalBridge Asp2-Lys7
Storage: unopened lyophilized vials are best stored refrigerated at 2–8°C, which is the storage method confirmed by our manufacturing partner and suitable for up to 24 months. Refrigeration is preferred because it minimizes unnecessary freeze–thaw cycles during routine handling. If substantially longer-term storage is required, unopened lyophilized vials may also be kept frozen. Once reconstituted, always store at 2–8°C and do not freeze.

Reconstitution and handling

PT-141 is supplied as a lyophilised vial and should be handled using standard peptide reconstitution procedures appropriate to the research setting. Must be reconstituted with bacteriostatic water before use. To help preserve structural integrity, add the chosen solvent slowly against the inside wall of the vial rather than directly onto the peptide cake, and avoid vigorous shaking. Gentle swirling is generally sufficient once the peptide has fully dissolved. Standard laboratory practice also includes allowing refrigerated vials to reach room temperature before reconstitution to minimise condensation inside the vial.

For other solvent selection, concentration planning and storage guidance, see the full Peptide Reconstitution Guide and Reconstitution Calculator.

Key published studies

Molinoff PB, Shadiack AM, Earle D, et al. PT-141: A Melanocortin Agonist for the Treatment of Sexual Dysfunction. Annals of the New York Academy of Sciences, 2003.

The foundational paper introducing PT-141 and describing its mechanism as a centrally acting melanocortin receptor agonist for sexual function research.

Diamond LE, Earle DC, Heiman JR, et al. An Effect on the Subjective Sexual Response in Premenopausal Women with Female Sexual Arousal Disorder by Bremelanotide (PT-141). Journal of Sexual Medicine, 2006.

A landmark clinical study investigating PT-141 in women with female sexual arousal disorder.

Kingsberg SA, Clayton AH, Portman D, et al. Bremelanotide for the Treatment of Hypoactive Sexual Desire Disorder. Obstetrics & Gynecology, 2019.

One of the pivotal Phase III clinical studies supporting the modern evidence base for Bremelanotide in HSDD.

Edinoff AN, et al. Bremelanotide for Treatment of Female Hypoactive Sexual Desire Disorder. Neurology International, 2022.

A comprehensive review covering pharmacology, mechanism of action, clinical efficacy and safety of PT-141.

Frequently Asked Questions

What is PT-141?

PT-141 (Bremelanotide) is a synthetic melanocortin receptor agonist derived from α-MSH. It is widely investigated in research on sexual desire, arousal and central nervous system signalling.

Why is PT-141 sometimes called Bremelanotide?

Bremelanotide is the international non-proprietary name (INN) for PT-141. Most published clinical studies use the name Bremelanotide, while researchers and peptide suppliers commonly refer to the same molecule as PT-141.

Is PT-141 the same as Melanotan II?

No. PT-141 was developed from Melanotan II but is designed to more selectively investigate melanocortin pathways involved in sexual function while reducing activity related to pigmentation. Although the two peptides share a common developmental history, they are now used for different areas of research.

How does PT-141 differ from Viagra® or Cialis®?

PT-141 acts primarily through central melanocortin pathways, whereas PDE-5 inhibitors work by enhancing blood flow through vascular mechanisms. These represent different biological approaches to sexual function research.

Why is PT-141 also called Bremelanotide?

Bremelanotide is the international non-proprietary name (INN) for PT-141. Most published clinical studies use the name Bremelanotide, while the peptide research community frequently refers to the molecule as PT-141.

What research areas commonly investigate PT-141?

Published studies have investigated PT-141 in sexual desire, sexual arousal, hypoactive sexual desire disorder, male sexual function, melanocortin receptor biology and neuroendocrine signalling.

Does PT-141 work through nitric oxide like PDE-5 inhibitors?

No. Current evidence indicates that PT-141 primarily acts through central melanocortin receptor activation rather than directly enhancing the nitric oxide–mediated vascular pathway targeted by PDE-5 inhibitors.

Is this product intended for human use?

No. PT-141 supplied by LIFE Peptide is provided strictly for laboratory and analytical research. It is not intended for human consumption, diagnosis, treatment or prevention of disease. Any discussion of published studies summarises the scientific literature relating to the PT-141 molecule rather than the intended use of this product.

Related research context

PT-141 belongs to the broader melanocortin and neuroendocrine peptide research category, focusing on central nervous system signaling and receptor-mediated behavioral pathways.
Researchers exploring related melanocortin pathway models may also examine:
Melanotan II — melanocortin receptor agonist research
Cognitive & neuroresearch peptides — CNS peptide signaling models
Growth hormone secretagogues — neuroendocrine pathway interaction research

NOTE: This is for educational reference only and does not constitute medical advice.

Disclaimer:
This product is sold for research purposes only. It is not intended to diagnose, treat, cure, or prevent any disease. Buyer assumes full responsibility for proper handling and use.

Sexual function research

PT-141 / 10 mg