Reconstituting means adding sterile water to a freeze-dried powder so it becomes a solution you can measure. It takes about five minutes. The part that matters most is knowing exactly how much water went in, because every dose is measured from that.
This is general bench technique, not medical advice and not an instruction to use any compound. It names no amounts. Follow the label and storage instructions that came with the product in front of you.
More water makes a weaker solution, which makes each dose a bigger, easier-to-read draw. Less water makes small doses hard to measure. The calculator shows the draw for any vial and water amount before you open anything.
Open the calculator →Read the label and confirm the amount. The powder should be dry, usually a white cake or loose powder. If the vial is cracked, the stopper is loose, or there is liquid inside already, do not use it.
Wash your hands. Pop the plastic caps off, wipe the rubber stopper of the vial and of the water with an alcohol swab, and let them dry for a few seconds.
Pull the amount you decided on into the syringe. Tap out large bubbles and push the plunger until the top of the liquid sits on the mark.
Push the needle through the vial's stopper and angle it so the water runs down the inside wall, not straight onto the powder. Many vials are under vacuum and will pull the water in; let it go slowly.
Roll the vial gently between your fingers or let it sit for a few minutes. Shaking makes foam and can damage the compound.
The solution should be clear with nothing floating in it. Cloudiness, flakes or a colour the supplier does not describe mean it should not be used.
Write the date and the concentration on the vial (for example, 10 mg in 2 mL is 5 mg per mL). Store it in the refrigerator, not the freezer, and follow the storage time the supplier states for that product.
Concentration is the amount in the vial divided by the water added. A 10 mg vial with 2 mL of water is 5 mg in every mL. On a U-100 insulin syringe one unit is a hundredth of a mL, so one unit of that solution holds 0.05 mg, which is 50 mcg. That is all the calculator does; it also tells you when the draw is too small to read or too large for the syringe.
Every draw after that is off by the same proportion. If the water changed, recalculate before drawing.
The same line means two and a half times as much liquid. Check the barrel says U-100.
1 mg is 1,000 mcg. A vial is usually labelled in mg and a dose in mcg, which is where a thousandfold slip comes from.
Both can break the compound down. Down the wall, then swirl.
Mixed solutions are kept cold. One left at room temperature for hours should be treated as spoiled.