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PT-141

From PeptidePlaza, the free peptide reference · Entry #010 · Nootropic · Hand-curated entry · Editorial standards

Research warning. FDA-approved medication (Vyleesi). Can cause transient increases in blood pressure. Not to be used more than 8 times per month. Contraindicated in uncontrolled hypertension.

PT-141 (also known as Bremelanotide, Vyleesi, Melanotan II metabolite) is a nootropic research peptide. A cyclic heptapeptide melanocortin receptor agonist and active metabolite of Melanotan II. Unlike peripheral vasodilators, PT-141 acts centrally via the CNS to modulate arousal and food intake pathways.

PT-141 (Bremelanotide) is a cyclic heptapeptide and metabolite of Melanotan II, acting as a non-selective melanocortin receptor agonist (MC1R, MC3R, MC4R, MC5R). Uniquely, it acts via the CNS rather than peripheral vasodilation — specifically through MC4R in the hypothalamus and limbic system to mediate arousal pathways. FDA-approved (2019) as Vyleesi for hypoactive sexual desire disorder (HSDD) in premenopausal women. Also studied for its role in appetite suppression via MC3R/MC4R, and tanning via MC1R.

1 Mechanism of action

Non-selective MC receptor agonism. MC4R activation in hypothalamus mediates arousal and appetite suppression; MC1R mediates melanogenesis; MC3R modulates energy balance and feeding behavior.

Primary targets: MC1R · MC3R · MC4R · MC5R

2 Reported effects

Effects below are those reported in the published literature cited on this page. They are not claims of clinical benefit and not medical advice.

2.1 Reported benefits

  • FDA-approved for hypoactive sexual desire disorder in women
  • CNS-mediated arousal pathway independent of vascular mechanisms
  • Appetite suppression effects via MC4R activation

2.2 Side effects

  • Nausea (reported in ~40% of patients in trials)
  • Flushing and injection site reactions
  • Transient increase in blood pressure

3 Chemical and physical properties

CAS number189691-06-3
Molar mass1025.18 g/mol
Purity (typical)>99.2%
Half-life~2.7 hours
Storage−20 °C, lyophilised powder, desiccated
SolubilitySterile water / bacteriostatic water
Receptors / targetsMC1R, MC3R, MC4R, MC5R

3.1 Amino acid sequence

Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-OH

4 Research dosages

1.75 mg SC as needed (FDA-approved); research protocols explore 0.75–2.5 mg dose range.

Dosages are reported from published protocols for reference only. Research chemicals are not for human consumption.

5 Research studies (8)

  1. Bremelanotide for Hypoactive Sexual Desire Disorder (RECONNECT Study)
    Obstetrics & Gynecology (2019) · RCT · N=1,247
    Phase 3 RCT supporting FDA approval. Bremelanotide SC improved FSDS-DAO score and satisfying sexual events vs placebo in premenopausal HSDD.
    Key finding: Bremelanotide significantly increased sexual desire scores and satisfying sexual events — led to FDA approval for HSDD.
  2. Central Nervous System Mechanisms of Melanocortin-Mediated Sexual Function
    Journal of Sexual Medicine (2007) · Review · N/A (review)
    Review of MC4R role in CNS-mediated arousal; pharmacological rationale for bremelanotide vs peripheral mechanisms.
    Key finding: MC4R activation in the hypothalamus directly mediates sexual arousal via distinct CNS pathways independent of vascular mechanisms.
  3. Comprehensive characterization of bremelanotide acetate and its degradants by LC-HRMS/MS and predicting epimerization through computational modelling
    Analytical methods : advancing methods and applications (2026) · Preclinical
    Overall, this study provides valuable insights into BRM stability behavior and supports peptide API/formulation development, impurity profiling, and quality control.
  4. Should Bremelanotide Be Considered for the Treatment of Sexual Arousal and Desire Disorders in Men?
    Journal of clinical psychopharmacology (2026) · Review
    Departments of Psychiatry and Behavioral Neurosciences, and Anesthesiology, Wayne State University School of Medicine, Detroit, MI.
  5. Bremelanotide
    (2006) · Review
    Until more data become available, bremelanotide should be used with caution during breastfeeding, especially while nursing a newborn or preterm infant.
  6. Female Syrian hamster analyses of bremelanotide, a US FDA approved drug for the treatment of female hypoactive sexual desire disorder
    Neuropharmacology (2025) · Preclinical
    If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
  7. Melanocortin Receptor Agonist Bremelanotide Induces Cell Death and Growth Inhibition in Glioblastoma Cells via Suppression of Survivin Expression
    Anticancer research (2024) · Preclinical
    The present results identified melanocortin receptors 3 and 4 as novel and viable therapeutic targets for glioblastoma.
  8. Small Effects, Questionable Outcomes: Bremelanotide for Hypoactive Sexual Desire Disorder
    Journal of sex research (2024) · Preclinical
    Across RECONNECT trial data from two prior publications and the current study, bremelanotide's benefits are statistically modest and limited to outcomes for which scant evidence of validity among women with HSDD exists.

6 Safety and risk profile

6.1 Regulatory status

PT-141 is currently classified as FDA approved. Approval applies to specific clinical indications and dosing; research-grade material is not the approved product.

Safety score: 75/100 — low concern. Derived from clinical data volume, known risks and regulatory status.

6.2 Contraindications

Conditions and populations in which use is contraindicated:

  • Uncontrolled hypertension (SBP >160 mmHg)
  • Cardiovascular disease with recent MI or stroke
  • Severe hepatic impairment
  • Pregnancy

6.3 Drug interactions

Drug or classInteractionRisk
AntihypertensivesTransient BP increases of 6 mmHg SBP / 3 mmHg DBP — may counteract antihypertensives.Moderate
Oral naltrexoneNaltrexone-containing products reduce bremelanotide Cmax by 30–40%.Moderate

6.4 Long-term risks

  • Skin hyperpigmentation with chronic use (MC1R agonism)
  • Blood pressure effects with frequent repeated dosing
  • Nevus/melanocyte changes with prolonged MC1R stimulation

6.5 Research best practices

  • Store at room temperature; lyophilized at −20 °C
  • Maximum frequency: 8 doses per month (per FDA labeling)
  • Administer 45 minutes before anticipated effect
  • Monitor blood pressure in hypertensive subjects
Safety data disclaimer. Safety assessments are based on published literature and are for educational reference only. Clinical evidence varies significantly between peptides. Always consult primary research and current regulatory guidance.

7 Frequently asked questions

How does PT-141 work differently from other compounds?
Unlike peripheral vasodilators that work via blood flow, PT-141 acts directly on the central nervous system through melanocortin receptors in the hypothalamus — the part of the brain that regulates arousal and desire. It does not require visual or physical stimulation to be effective.
What is the FDA status of PT-141?
PT-141 (Bremelanotide) is FDA-approved under the brand name Vyleesi for hypoactive sexual desire disorder (HSDD) in premenopausal women. It is administered as a subcutaneous injection 45 minutes before anticipated activity.

8 References

  1. Comprehensive characterization of bremelanotide acetate and its degradants by LC-HRMS/MS and predicting epimerization through computational modelling PubMed (2026). Yuvaraaj VK, et al.. View source
  2. Should Bremelanotide Be Considered for the Treatment of Sexual Arousal and Desire Disorders in Men? PubMed (2026). Pfaus JG, et al.. View source
  3. Bremelanotide PubMed (2006). View source
  4. Female Syrian hamster analyses of bremelanotide, a US FDA approved drug for the treatment of female hypoactive sexual desire disorder PubMed (2025). Borland JM, et al.. View source

Related compounds

Entries that share a target, a mechanism, or a research area with PT-141.

Melanotan IInootropic

Also targets MC1R

A potent cyclic analog of α-MSH that activates melanocortin receptors broadly. Studied for UV-independent melanogenesis, appetite suppression, and as the parent compound of PT-141 (Bremelanotide).

Semaxnootropic

Also targets MC4R

A synthetic analog of a fragment of ACTH that lacks hormonal activity but retains potent neuroprotective and cognitive-enhancing properties. Widely used in Russian clinical settings for stroke, memory, and attention disorders.

CagriSemapeptide blends

Shares activation and hypothalamus pharmacology

The first amylin + GLP-1 fixed-dose combination to reach phase 3. Two satiety systems in one weekly injection, and the closest any injectable has come to bariatric-surgery-range weight loss.

Setmelanotideapproved

Shares mc4r and hypothalamus pharmacology

A cyclic octapeptide that restores signalling in a broken melanocortin pathway. The only obesity drug that treats a specific genetic lesion rather than appetite in general.

Survodutidemetabolic

Shares agonism and energy pharmacology

A 29-amino-acid dual agonist that pairs GLP-1 appetite suppression with glucagon-driven energy expenditure and hepatic fat oxidation. Its liver-fat data is the standout: up to 63% reduction.

Selanknootropic

Shares modulates and balance pharmacology

A synthetic analog of the endogenous tetrapeptide Tuftsin. Developed by the Russian Institute of Molecular Genetics. Studied for anxiolytic, nootropic, and immunomodulatory effects without sedation or dependence.

9 See also

For research reference only. Not medical advice. Peptides may be regulated or restricted in your jurisdiction. Entry validated by the PeptidePlaza Biomedical Research Desk; see editorial standards.

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