PT-141 Dosage Calculator
PT-141 is bremelanotide, approved as Vyleesi in a 1.75 mg autoinjector for premenopausal women with hypoactive sexual desire disorder. Research and compounded versions come as a 10 mg dry-powder vial, so the label dose has to be converted to units.
This page shows that conversion at each common water volume and flags the point where the draw does not fit a small syringe.
FDA labelAn approved product exists and its label states the dose. · Reviewed by the FormBlends Editorial Standards Team · 2026-09-03
FDA labelLabel: 1.75 mg under the skin at least 45 minutes before anticipated activity, no more than one dose in 24 hours and eight per month.
Draw to
36 units
exactly 35 units; nearest mark is 36 (+2.9%)
Volume
0.35 mL
1 unit = 0.01 mL on a U-100 syringe
Concentration
5 mg/mL
50 mcg in every unit
Doses per vial
5
about 5 days at this frequency
The exact draw is 35 units, which sits between the 2-unit marks on this syringe. Drawing to 36 is 2.9 percent over. A 0.5 mL syringe has finer marks.
How much water should I use for this dose?
Volumes that put your dose on a printed mark of the 1 mL syringe, inside the accurate part of the barrel.
Embed this calculator on your site
Free to embed with the FormBlends attribution link. Paste this where you want the calculator to appear.
FDA compounding status (2026-08-24): Component of an approved drug. Component of Vyleesi; same essentially-a-copy constraint; cited in the 08/24/2026 Peptide Partners letter.. Full status table and sources
What the PT-141 dose evidence actually is
Label: 1.75 mg under the skin at least 45 minutes before anticipated activity, no more than one dose in 24 hours and eight per month.
The Vyleesi label specifies 1.75 mg subcutaneously in the abdomen or thigh at least 45 minutes before anticipated sexual activity, no more than one dose in 24 hours and no more than eight doses per month. Nausea is the most common side effect and the label notes a transient blood pressure rise.
Compounded PT-141 is used off-label in men and women at doses from 0.5 mg to 2 mg in forum protocols. The label dose is the only one with a trial program behind it.
PT-141 units at each water volume
The table uses a 10 mg vial. Each cell is the draw on a U-100 insulin syringe for that dose at that water volume. Cells above 100 units do not fit a 1 mL syringe; cells below 10 units sit in the part of a 1 mL barrel where measurement error rises, and a 0.5 mL or 0.3 mL syringe reads them better.
| Dose | 10 mg + 1 mL10 mg/mL | 10 mg + 2 mL5 mg/mL | 10 mg + 3 mL3.333 mg/mL | 10 mg + 5 mL2 mg/mL |
|---|---|---|---|---|
| 1.75 mg | 17.5 units | 35 units | 52.5 units | 87.5 units |
| 3.5 mg | 35 units | 70 units | 105 (does not fit) | 175 (does not fit) |
| 7 mg | 70 units | 140 (does not fit) | 210 (does not fit) | 350 (does not fit) |
Worked example: 10 mg with 2 mL is 5 mg per mL, so 1.75 mg (1.75 mg, the Vyleesi labelled dose) is 36 units, or 0.35 mL.
Mixing PT-141
A 10 mg vial with 2 mL gives 5 mg per mL, so 1.75 mg is 35 units and 1 mg is 20 units. With 1 mL the same doses are 17.5 and 10 units, and 17.5 units lands between the marks on a 1 mL syringe; a 0.5 mL syringe reads it cleanly.
Storing PT-141 after mixing
Refrigerate after mixing. A 10 mg vial at 1.75 mg is five doses, and with the label's eight-per-month cap it will usually be used up inside 28 days.
PT-141 calculator questions
How many units is 1.75 mg of PT-141?
Thirty-five units at 5 mg per mL (10 mg in 2 mL), 17.5 units at 10 mg per mL (10 mg in 1 mL).
How much bac water for 10 mg PT-141?
Two millilitres puts the label dose at 35 units, an easy read on any syringe. One millilitre halves the draw and lands it on a half unit.
How long before activity is PT-141 taken?
The Vyleesi label says at least 45 minutes before anticipated activity, with a limit of one dose per 24 hours and eight per month.
Is the nasal spray dosed the same way?
No. Nasal PT-141 products are compounded at their own concentrations and are not covered by the injectable label. This calculator is for injectable vials only.
Sources
PT-141 guide
Evidence, mechanism, side effects and regulatory status.
PT-141 through FormBlends
Provider review, licensed pharmacy, labelled concentration.
The full peptide calculator
All peptides, pre-mixed vials, blends, mistakes and concentration changes.
Free downloads built from this calculator's math
Peptide Dosing and Reconstitution Chart 2026
20 pages, 12 peptides, every vial size, units at five water volumes, printable vial labels. PDF.
Bacteriostatic Water Cheat Sheet
How much to add, what one unit holds, the 28-day rule stated correctly, four mistakes to avoid. PDF.
28-Day GLP-1 Injection Tracker
Dose, units drawn, site, weight, side effects and the vial counting down. PDF and spreadsheet.
Other peptide calculators
Arithmetic only. This page converts the dose you enter into units and millilitres. It does not recommend a dose. PT-141 is a prescription medication; follow your label. FormBlends connects patients with licensed providers and pharmacies and does not prescribe or dispense.
