PT-141
also known as Bremelanotide, Vyleesi, PT 141
Cyclic 7-amino-acid peptide and MC4R-selective agonist derived from α-MSH. FDA-approved 2019 (Vyleesi) for hypoactive sexual desire disorder in pre-menopausal women — the first centrally-acting peptide for sexual dysfunction. Acts on hypothalamic melanocortin pathways to drive arousal independent of vascular pathways (unlike PDE5 inhibitors).
At a glance
SQ · Abdomen / thigh · ≥45 min before sex
Mechanism
Primary target — Melanocortin-4 receptor (MC4R) in hypothalamus [simerly-2023][fda-vyleesi-label-2019].
Pathway — MC4R agonism in paraventricular nucleus → autonomic + neuroendocrine sexual arousal pathways [simerly-2023].
Downstream effect — Increased sexual desire and arousal; central rather than peripheral mechanism [clayton-2015].
Origin — Cyclic 7-AA peptide derived from α-MSH (agonist Ac-Nle-Asp-His-D-Phe-Arg-Trp-Lys-OH cyclic) [fda-vyleesi-label-2019].
Dosage
Protocols described in the cited literature; not medical advice.
| Parameter | Value |
|---|---|
| Standard dose | 1.75 mg SQ [fda-vyleesi-label-2019]Single dose ≥45 min before anticipated sexual activity. Max 1 dose / 24 hr. |
| Frequency | PRN, max 8 doses / month |
| Lower / starter dose | 1 mg (off-label) |
| Evidence basis | FDA-approved (HSDD pre-menopausal women) [fda-vyleesi-label-2019][clayton-2015] |
| Duration | PRN; reassess if no benefit after 8 doses |
| Reconstitution | Pre-filled commercial pen (Vyleesi). Research vial: bacteriostatic water. |
| Timing | ≥45 min before sexual activity |
| Half-life | ~2.7 hr [fda-vyleesi-label-2019] |
Reconstitution
A pure mass-to-volume utility. Enter what you have in the vial; the atlas computes the volume per dose. No prescription information.
Adverse events
Severities follow the FDA / CTCAE convention.
- — Uncontrolled hypertension
- — Known cardiovascular disease (caution)
- — Pregnancy
- — Pre-existing hyperpigmentation disorders
- — MC4R-pathway-dependent psychiatric conditions
Administration
- 01Reconstitution
Vyleesi: pre-filled auto-injector. Research vial: 2 mL bacteriostatic water per 10 mg → 5 mg/mL.
- 02Injection site
SQ — abdomen or thigh.
- 03Timing
≥45 min before sexual activity for peak effect. Effect persists ~6–8 h.
- 04Storage
Vyleesi: room temp ≤30 °C. Research vial: refrigerate after reconstitution.
- 05Needle
Auto-injector (Vyleesi) or 29–31G, 4–8 mm insulin syringe.
Sources
of 41 rendered claims carry a resolvable citation.
- [clayton-2015]Clayton 2015 — Bremelanotide for female sexual dysfunctions in premenopausal women
J Sex Med, 2015 - [fda-vyleesi-label-2019]VYLEESI (bremelanotide injecti 2019 — VYLEESI (bremelanotide injection) prescribing information
fda-label, 2019 - [simerly-2023]Simerly 2023 — Bremelanotide (PT-141): clinical pharmacology + safety review
Sex Med Rev, 2023