How much BAC water do I add to PT-141?

For a 10 mg PT-141 vial, add 2 mL of bacteriostatic water. This yields a concentration of 5 mg/mL (5000 mcg/mL), which is the standard research concentration.

What is the PT-141 syringe draw for 1 mg?

With a 10 mg vial reconstituted in 2 mL BAC water (5 mg/mL): a 1 mg dose = 0.2 mL = 20 IU on a U-100 insulin syringe. For 1.75 mg draw to the 35 IU line.

Can you use sterile water instead of BAC water for PT-141?

You can, but bacteriostatic water is preferred. BAC water allows you to draw from the vial multiple times safely over 28 days. Sterile water must be used in a single session only.

How do you inject PT-141?

PT-141 is administered subcutaneously (SC), typically in the lower abdomen or flank. Use a short (5/16 inch) insulin syringe. Pinch the skin, insert at 45 degrees, inject slowly, and apply gentle pressure after withdrawal.

Guides

Reconstitution

PT-141 Reconstitution Guide

Q: How long does reconstituted PT-141 last?

Reconstituted PT-141 is stable for 4–6 weeks when refrigerated at 2–8°C and protected from light. Do not freeze a reconstituted vial.

PT-141 (bremelanotide) is a melanocortin receptor agonist. Reconstituting it correctly ensures accurate dosing and vial longevity across your protocol.

Quick setup - 10 mg vial + 2 mL BAC water = 5 mg/mL. For a 1 mg dose: draw to 20 IU. For 1.75 mg: draw to 35 IU. Refrigerate. Good for 4–6 weeks.

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Step by Step

How to Reconstitute PT-141

Let the vial reach room temperature

If stored frozen, allow the lyophilized PT-141 vial to sit at room temp for 10–15 minutes before adding water.

Swab both vials

Wipe the rubber stoppers of the PT-141 vial and the BAC water vial with alcohol swabs. Let dry for 10 seconds.

Draw 2 mL of BAC water

Pull back the syringe plunger to the 200 IU line on a U-100 syringe (= 2 mL). This is the standard volume for a 10 mg vial.

Inject slowly down the inside wall

Insert the needle and press the plunger slowly, directing the stream against the glass wall - not directly onto the powder cake.

Swirl gently until dissolved

PT-141 dissolves quickly. Swirl the vial gently. Never shake - agitation degrades the peptide structure.

Label and refrigerate

Write the date and concentration (5 mg/mL) on the vial. Store at 2–8°C, away from light. Good for 4–6 weeks.

Dose Reference

Common PT-141 Draws (10 mg vial + 2 mL BAC)

Concentration: 5 mg/mL (5000 mcg/mL)

Dose	Volume (mL)	Syringe Draw (IU)
0.5 mg (500 mcg)	0.10 mL	10 IU
1.0 mg (1000 mcg)	0.20 mL	20 IU
1.25 mg (1250 mcg)	0.25 mL	25 IU
1.75 mg (1750 mcg)	0.35 mL	35 IU
2.0 mg (2000 mcg)	0.40 mL	40 IU

Use the calculator to verify any vial size or BAC water volume - the table above is for a standard 10 mg / 2 mL setup only.

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Storage

After Reconstitution

Refrigerate at 2–8°C - stable for 4–6 weeks reconstituted

Protect from light - store in the original vial box or wrap in foil

Do not freeze a reconstituted vial - ice crystals degrade the peptide

Discard if cloudy or discolored - clear solution is expected; cloudiness indicates contamination

FAQ

Common Questions

How much BAC water do I add to a 10 mg PT-141 vial?

Add 2 mL of bacteriostatic water to a 10 mg vial. This produces a 5 mg/mL (5000 mcg/mL) concentration. For a 5 mg vial, use 1 mL BAC water for the same 5 mg/mL result.

What syringe line is 1 mg of PT-141?

With a 10 mg vial reconstituted in 2 mL BAC water: 1 mg = 20 IU on a U-100 insulin syringe. 1.75 mg = 35 IU. Verify your exact dose using the ASCEND calculator if your vial size or water volume differs.

Can I use sterile water instead of BAC water?

Yes, but sterile water has no antimicrobial preservative. You must use the entire reconstituted vial in a single session. BAC water is preferred for multi-draw protocols lasting weeks.

How long does reconstituted PT-141 last?

Refrigerated PT-141 reconstituted with BAC water is stable for 4–6 weeks. Never freeze a reconstituted vial. Discard immediately if the solution becomes cloudy.

Where is PT-141 injected?

PT-141 is given subcutaneously (SC) - typically in the lower abdomen or flank. Use a short insulin needle (5/16 in), pinch the skin, inject at 45 degrees, and apply light pressure after withdrawal.

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