PT-141 (Bremelanotide) (10mg)

PT-141 (Bremelanotide) is a **cyclic heptapeptide**—a metabolite of Melanotan II, but without its tanning effect—that acts as a **melanocortin 4 receptor (MC4R) agonist** in the hypothalamus and limbic system. By activating MC4R, it triggers neuronal pathways for sexual arousal via **dopaminergic and oxytocinergic signaling** in the paraventricular nucleus (PVN). Unlike PDE5 inhibitors (Viagra, Cialis), which act **vascularly** on the genitals, PT-141 acts **centrally** in the brain, increasing sexual **desire** (desire), and not just physical response. This makes it effective even in patients who do not respond to PDE5i. Its action begins ~45 minutes after administration and lasts for 6–12 hours.

• Typical dose: 1–2mg subcutaneously, as needed
• Frequency: 45 minutes before sexual activity, maximum 1x/24h
• Storage: 2–8°C after reconstitution

1. Clean the vial tops with an alcohol swab.
2. Draw 2mL of bacteriostatic water.
3. Slowly inject into the side wall of the vial.
4. Gently swirl until fully dissolved.
5. Store in the refrigerator (2–8°C).

• PT-141 (Bremelanotide) is a cyclic heptapeptide, a metabolite of Melanotan II, that acts as an MC4R (melanocortin 4 receptor) agonist in the hypothalamus.
• FDA-approved (2019) as Vyleesi® — the only approved drug for hypoactive sexual desire disorder (HSDD) in premenopausal women.
• Acts via a central nervous mechanism — it increases sexual desire (desire), unlike PDE5i (Viagra/Cialis) which only improve the physical response.
• RECONNECT (Phase III) clinical studies showed a significant increase in satisfying sexual events and a decrease in distress in women with HSDD.
• Also effective in men — studies show improved erections in patients who do not respond to PDE5i.

• Test dose: 0.5mg — to assess tolerance (mainly nausea).
• Typical dose: 1–1.75mg subcutaneously, 45 minutes before sexual activity.
• FDA maximum dose: 1.75mg/dose.
• Maximum: 1 dose per 24 hours, ≤8 doses/month (FDA guideline).
• Cycling is not required — use as needed (PRN).
• Break between cycles: A strict washout period is not required due to its as-needed use. However, the FDA recommends ≤8 doses/month to prevent MC4R desensitization. In case of long-term use, a 2–4 week break can restore optimal response.

• Reconstituted: 2–8°C, use within 28 days.
• Lyophilized powder: store at room temperature or in the refrigerator, away from light.
• Do not freeze after reconstitution.

• Nausea is the most common side effect (~40%) — significantly reduced with a lower starting dose.
• Contraindicated in uncontrolled hypertension or known cardiovascular disease.
• May cause transient skin hyperpigmentation (melanotropic action) — resolves after discontinuation.
• Avoid concomitant use with naltrexone (opposing action on the MC4R pathway).
• This protocol is for informational purposes only.

1. FDA Approval — Vyleesi — Simon JA, et al. Bremelanotide for hypoactive sexual desire disorder in premenopausal women. Obstet Gynecol. 2019;134(5):899-908.
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2. RECONNECT Phase III Trial — Kingsberg SA, et al. Bremelanotide for the treatment of HSDD in premenopausal women: two randomized clinical trials. N Engl J Med. 2019;381(14):1346-1356.
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3. MC4R Mechanism — Molinoff PB, et al. PT-141: a melanocortin agonist for the treatment of sexual dysfunction. Ann N Y Acad Sci. 2003;994:96-102.
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4. Male Erectile Dysfunction — Diamond LE, et al. An effect on the subjective sexual response in premenopausal women with sexual arousal disorder by bremelanotide (PT-141). J Sex Med. 2006;3(4):628-638.
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5. Safety & Pharmacology Review — Clayton AH, et al. Bremelanotide for female sexual dysfunctions. Expert Opin Pharmacother. 2020;21(8):881-892.
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