Retatrutide Reconstitution & Dosing Protocol (With Calculator)

Why reconstitution accuracy matters

Retatrutide ships as a lyophilized powder because peptides in solution degrade. The powder is stable for months in a sealed vial; once bacteriostatic water is added, the clock starts. Every downstream number in a research protocol — concentration, draw volume, doses per vial — flows from the two values you choose at reconstitution.

The core formula

Concentration (mg/mL) = vial strength (mg) ÷ bacteriostatic water (mL).

Draw volume (mL) = target dose (mg) ÷ concentration.

On a U-100 insulin syringe, 1.0 mL equals 100 units, so units = draw volume × 100. A 10 mg vial reconstituted with 2 mL gives 5 mg/mL; a 2 mg research dose is 0.4 mL, or 40 units.

Choosing your water volume

More bacteriostatic water does not change how much peptide is in the vial — it only changes how far each dose spreads across the syringe barrel. Small doses measured at 2–3 units carry large percentage error; diluting to spread the same dose across 15–25 units materially improves precision.

Storage after reconstitution

Store the reconstituted vial at 2–8 °C, upright, protected from light, and avoid freeze-thaw cycles. Bacteriostatic water contains 0.9% benzyl alcohol, which permits multiple entries. Sealed lyophilized vials are the stable form — reconstitute only what a working window requires.

Handling checklist

• Alcohol-wipe both stoppers and let them dry.
• Inject water down the vial wall, never onto the powder cake directly.
• Swirl until clear; never shake, which shears the peptide.
• Label the vial with the reconstitution date and resulting concentration.
• Discard immediately if the solution is cloudy or contains particulates.

For laboratory and research use only. Not for human or veterinary use.