PT-141 reconstitution calculator

What the FDA-approved product actually is — and why it doesn't need this tool

PT-141 is the research/compounding-market name for bremelanotide. Its FDA-approved branded product, Vyleesi, was approved under NDA 210557 in 2019 for acquired, generalized hypoactive sexual desire disorder (HSDD) in premenopausal women — read directly off FDA's own Drugs@FDA record — not a general libido or sexual-performance product, and not indicated for men. Its label, confirmed on DailyMed, describes a 1.75 mg/0.3 mL single-dose autoinjector that ships pre-filled and ready to use. There is no diluent step on Vyleesi's own label at all — a patient using the approved product never reconstitutes anything, so this calculator has nothing to check against Vyleesi's own instructions.

What the calculator above is actually for is the separate compounded/research-market product also called PT-141: sterile lyophilized (freeze-dried) powder sold in a vial, which a buyer reconstitutes with bacteriostatic water before drawing up a subcutaneous dose. That is a materially different product from Vyleesi's pre-filled pen, not a generic copy of the same delivery form — and worth noting, compounding a copy of a commercially available FDA-approved drug is restricted under federal law unless that drug is currently on FDA's drug shortage list; multiple 2026 industry sources report bremelanotide is not currently on that list, which is part of why some compounding pharmacies decline to prepare it. This calculator does the vial-to-syringe arithmetic on whatever numbers you enter for the powder-vial product — it cannot confirm that vial's contents, purity, legal status, or source.

Sources: openFDA Drugs@FDA record for VYLEESI (bremelanotide acetate), NDA 210557, and the DailyMed structured product label for VYLEESI, both fetched 2026-08-02. View the Drugs@FDA record on openFDA.