PT-141 peptide calculator
A 10 mg PT-141 vial mixed with 2 ml of bacteriostatic water holds 5 mg/ml. A 1.75 mg dose is 0.35 ml — 35 units on a U-100 insulin syringe — and the vial holds 5 doses of that size.
PT-141 dosage chart: units to draw
Units on a U-100 insulin syringe (100 units = 1 ml) for PT-141 doses from 500 mcg to 2 mg, by how much bacteriostatic water is in a 10 mg vial. The highlighted row is the 1.75 mg dose used above.
| Dose | 1 ml water 10 mg/ml | 2 ml water 5 mg/ml | 3 ml water 3.33 mg/ml | Doses per vial |
|---|---|---|---|---|
| 500 mcg | 5 u 0.050 ml | 10 u 0.10 ml | 15 u 0.15 ml | 20 |
| 1.75 mg | 18 u 0.17 ml | 35 u 0.35 ml | 53 u 0.53 ml | 5 |
| 2 mg | 20 u 0.20 ml | 40 u 0.40 ml | 60 u 0.60 ml | 5 |
A 35-unit draw fits a 0.5 ml insulin syringe (50-unit capacity) with 1-unit markings.
Unit math only, not a dosing recommendation. The dose range is what published protocols and trials describe; see the PT-141 guide for sources.
How to reconstitute PT-141
- Wipe both vial stoppers with a fresh alcohol swab and let them dry.
- Draw 2 ml of bacteriostatic water into a syringe.
- Insert the needle at an angle into the PT-141 vial and let the water run slowly down the inner wall — do not inject directly onto the powder.
- Do not shake. Gently swirl the vial until the peptide fully dissolves.
- Storage for PT-141: Lyophilized refrigerated. Reconstituted: refrigerated, use within 28 days.
- For a 1.75 mg dose, draw to the 35-unit mark (0.35 ml) on a U-100 insulin syringe.
About PT-141
PT-141 (bremelanotide) is a synthetic melanocortin receptor agonist developed from melanotan II. It acts on central nervous system pathways rather than the vascular system to enhance sexual arousal.
Half-life: Approximately 2.7 hours (range 1.9–4 hours); blood levels peak about 1 hour after a subcutaneous injection
Typical dose range: 1.75 mg (1750 mcg) per dose on demand, per the Vyleesi label; 0.5–2 mg in other reports
Class: Melanocortin receptor agonist (MC3R / MC4R)
Regulatory status: FDA approved as Vyleesi for hypoactive sexual desire disorder (HSDD) in premenopausal women.
Read the full PT-141 guide → — mechanism, side effects, storage, regulatory status and citations. Or browse the whole peptide glossary.
Other tools for PT-141
Need a different unit or a different question? The peptide dose converter moves a dose between mcg, mg and IU, and the PT-141 half-life chart shows how concentration accumulates across a dosing cadence. Loading PT-141 into a reusable 3 ml pen instead of drawing it with a syringe? The peptide pen calculator turns the same vial into mcg per click and clicks to dial. All of them are listed on the free peptide tools page.
PT-141 calculator FAQ
Is this a PT-141 peptide calculator or a reconstitution calculator?
Both. This PT-141 calculator converts vial strength, bacteriostatic-water volume, and target dose into milliliters and insulin-syringe units. It does not recommend a medical dose.
How much bacteriostatic water for a 10 mg PT-141 vial?
This page is pre-filled with 2 ml of bacteriostatic water for a 10 mg PT-141 vial because that is a common research ratio. You can adjust the water amount in the full calculator.
How many units is a 1.75 mg PT-141 dose?
35 units on a U-100 insulin syringe, when a 10 mg vial is mixed with 2 ml of bacteriostatic water (5 mg/ml). That is 0.35 ml. With a different amount of water the unit count changes — the dose chart on this page lists 1 ml, 2 ml, 3 ml mixes.
How many doses are in a 10 mg PT-141 vial?
5 doses of 1.75 mg. The number of doses depends only on vial strength and dose size — adding more or less water changes the volume of each draw, not how many draws the vial holds.
Does this PT-141 dosage calculator give medical advice?
No. It only performs unit math. Dosing, titration, and whether PT-141 is appropriate are clinical decisions that should be made with a licensed healthcare professional.
Skip the math — let the app handle it
Peptide Protocol remembers your PT-141 vial, shows the units for every dose, tracks what is left, and rotates injection sites for you.
Get the iPhone app →Educational use only. Peptide Protocol is an informational tool. Nothing on this page constitutes medical advice. Many peptides are prescription-only or restricted in your jurisdiction. Always consult a licensed healthcare professional before injecting any compound.