PT-141 (Bremelanotide) — Clinical Reference

**⚠ Educational reference only — not medical advice.** This article is for research and educational reference. Always consult your own physician before considering any peptide protocol. See the full Disclaimer at the end of this article. ## Introduction PT-141 (bremelanotide) is a synthetic seven-amino-acid analogue of α-melanocyte-stimulating hormone, developed from melanotan-II for sexual-dysfunction indications. FDA-approved as **Vyleesi** for hypoactive sexual desire disorder (HSDD) in premenopausal women; off-label use in men and other populations is widespread. ## Mechanism of Action Non-selective agonist at melanocortin receptors, with relatively higher activity at MC4R and MC3R. The therapeutic effect in HSDD is CNS-mediated rather than peripheral, modulating dopaminergic pathways that regulate sexual motivation. The compound does **not** act through the vascular nitric-oxide pathway exploited by PDE-5 inhibitors. ## Approved and Investigated Indications Approved: HSDD in premenopausal women (single-dose, as-needed). Off-label/investigational: male erectile dysfunction (particularly in PDE-5-inhibitor non-responders), female sexual interest/arousal disorder more broadly, adjunct in psychosexual therapy. ## Reconstitution The approved **Vyleesi product is a pre-filled autoinjector** containing 1.75 mg in 0.3 mL — no reconstitution required. For compounded/research-grade lyophilized product: typical **10 mg vial** add **2 mL of bacteriostatic water**, swirl gently. Final concentration **5000 mcg/mL (5 mg/mL)** — each 0.35 mL (35 units on a U-100 insulin syringe) delivers ~1.75 mg. ## Dosing Protocol (research literature) **Approved Vyleesi protocol**: **1.75 mg subcutaneously as a single dose at least 45 minutes prior to anticipated sexual activity**, with **no more than 1 dose per 24 hours and no more than 8 doses per month**. Off-label male protocols typically use similar single-dose subcutaneous regimens at 1–2 mg. ## Administration Subcutaneous injection into the abdomen or thigh. Effect onset 30–60 minutes; window of activity several hours. ## Storage & Handling Vyleesi autoinjector: room temperature per labeling. Compounded lyophilized: refrigerate (2–8°C). Reconstituted: refrigerate; stable approximately **28 days**. Protect from light. ## Side Effects **Nausea is notable** — affects roughly 40% in clinical trials and is the most common reason for discontinuation. Other: flushing, headache, injection-site reaction, transient focal hyperpigmentation. **Blood-pressure effects**: transient elevation in systolic and diastolic BP with reflex heart-rate decrease. ## Contraindications Uncontrolled hypertension, cardiovascular disease, concurrent use of medications that raise blood pressure significantly. Caution in patients prone to hyperpigmentation. Pregnancy, lactation. ## Monitoring Baseline blood pressure on at least two occasions and cardiovascular risk assessment. Re-check blood pressure if patient reports symptoms suggestive of hypertensive effect. Skin examination if pigmentation changes reported. ## Disclaimer **This article is for informational and research-reference purposes only.** Nothing in this document constitutes medical advice, a prescription, or a recommendation from a physician. The reconstitution, dosing, and protocol information above reflects ranges commonly cited in published research and clinician-directed protocols — it is provided as reference material only, not as instructions, an endorsement of off-label use, or a substitute for individualized medical evaluation. **Customers should do their own research and consult their own physician** before considering any peptide protocol. Whether a given compound is appropriate for an individual — and at what dose, for what duration, and alongside what monitoring — is a decision that only a licensed clinician with knowledge of that individual's medical history, current medications, and conditions can make. The platform and the author make no claim that any compound described here is safe, effective, or appropriate for any particular person or purpose, and accept no responsibility for outcomes arising from self-directed use of the information.