PT-141 dosage calculator
In a 10 mg vial with 2 mL of water (5 mg/mL), 1 mg of PT-141 is 20 units on a U-100 insulin syringe. PT-141 is dosed as needed rather than daily, usually 0.5 to 2 mg an hour or two beforehand.
25 printable pages: dosing cards for the twelve most-used compounds at three water volumes, titration planners, a vial log, and five pages on what to do when it has already gone wrong.
Dose to units at the usual vial and water
| Dose | U-100 units | Draw | Doses per vial | Vial lasts |
|---|---|---|---|---|
| 0.5 mg | 10 units | 0.1 mL | 20 | 20 uses |
| 0.75 mg | 15 units | 0.15 mL | 13 | 13 uses |
| 1 mg | 20 units | 0.2 mL | 10 | 10 uses |
| 1.5 mg | 30 units | 0.3 mL | 6 | 6 uses |
| 1.75 mg | 35 units | 0.35 mL | 5 | 5 uses |
| 2 mg | 40 units | 0.4 mL | 5 | 5 uses |
10 mg vial in 2 mL of bacteriostatic water (5 mg/mL), U-100 insulin syringe, as needed.
About PT-141
PT-141 is bremelanotide, a melanocortin receptor agonist. It is a licensed medicine (Vyleesi) at 1.75 mg by subcutaneous autoinjector for hypoactive sexual desire disorder in premenopausal women, with a limit of one dose in 24 hours and eight a month. Research vials of 10 mg are sold outside that licence, for both sexes.
A 10 mg vial with 2 mL of water is 5 mg/mL, so 1 mg is 0.2 mL, or 20 units, and the licensed 1.75 mg is 35 units. Nausea is the most reported side effect and scales with dose, which is why most people who use it start at the low end. It raises blood pressure transiently; the licence excludes people with uncontrolled hypertension.
The same 10 mg vial at other water volumes
If the draw is awkward to read, change the water, not the dose. The dose stays the same; only the mark moves.
| Vial | BAC water | Concentration | Draw | U-100 units | Doses/vial |
|---|---|---|---|---|---|
| 10 mg | 1 mL | 10 mg/mL | 0.1 mL | 10 units | 10 |
| 10 mg | 2 mL | 5 mg/mL | 0.2 mL | 20 units | 10 |
| 10 mg | 3 mL | 3.33 mg/mL | 0.3 mL | 30 units | 10 |
All rows above assume a 1 mg dose and a standard U-100 insulin syringe, where 100 units = 1 mL.
How long it lasts in the body
The half-life of PT-141 is about 2.7 hours. That is the time for the amount in your blood to halve, so after one half-life you are at 50 percent of the peak, after two you are at 25 percent, and after four you are at roughly 6 percent. It is cleared the same day, so there is no build-up between uses and nothing left over by the next one; the effect window is a few hours after each dose.
Common questions
- How many units is 1 mg of PT-141?
- It depends entirely on how much water you added. In a 10 mg vial reconstituted with 2 mL, the concentration is 5 mg/mL, so 1 mg is 0.2 mL, which is 20 units on a U-100 insulin syringe. In the same vial with 1 mL of water it is 10 units, and with 3 mL it is 30 units.
- How much bacteriostatic water for a 10 mg PT-141 vial?
- 2 mL is the usual choice. It gives 5 mg/mL, which puts the commonly reported range of 0.5 mg to 2 mg between roughly 10 and 40 units. Aim for a draw between about 10 and 50 units, where the barrel is easiest to read, and add or remove water to get there.
- How many doses are in a 10 mg vial?
- Divide 10 by your dose. At 1 mg that is 10 doses.
- How many units is 1 mg of PT-141?
- In a 10 mg vial with 2 mL of water, 20 units on a U-100 syringe. The licensed 1.75 mg dose is 35 units at that concentration.
- How long before does PT-141 need to be taken?
- The licensed product is taken at least 45 minutes before. Reports commonly describe one to two hours. The half-life is about 2.7 hours.
Buying PT-141?
Peptulator does not list, rank or link vendors. Whoever the supplier is, use the strength printed on your own vial and check the batch certificate of analysis before you rely on any number here.
Common conversions
The same three-step maths, pre-filled for the doses people ask about most. Units on a U-100 insulin syringe, where 100 units is 1 mL.
- mg to units calculator Any dose at any concentration, both directions, with the full reference tables
- Units to mg calculator What the units you drew are in milligrams
- 1 mg to units The most-asked conversion, at every common setup
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