What you need before starting
A vial of lyophilised retatrutide, bacteriostatic water, an alcohol swab, and a syringe sized appropriately for the water volume you’re adding (commonly a 1-3mL syringe for the water, separate from the insulin syringe used later to draw doses).
Why bacteriostatic water specifically
Bacteriostatic water contains a small amount of benzyl alcohol that helps inhibit bacterial growth in the mixed solution over its usable life, which is why it’s preferred over plain sterile water for a vial that will be used across multiple doses.
The process
Swab both the retatrutide vial top and the bacteriostatic water vial top with alcohol. Draw the chosen water volume into the syringe. Insert the needle into the retatrutide vial at an angle, and let the water run gently down the inside wall of the vial rather than injecting it directly onto the powder.
Why gentle addition matters
Injecting water forcefully directly onto the powder can cause excess foaming and may damage the peptide structure through mechanical stress. Letting it run down the glass and swirling (not shaking) the vial afterward dissolves the powder more gently.
After mixing
Let the vial sit for a minute or two if any powder hasn’t fully dissolved, then swirl gently again. Once clear, label the vial with the reconstitution date and the water volume used, and refrigerate it promptly.