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The reconstitution maths, done once and correctly

Vial amount plus diluent volume gives you concentration, draw volume, syringe units and how many draws a vial holds.

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The calculation you redo on a notepad every week, done right in two fields — including the syringe-unit conversion people most often get wrong.

Concentration, both ways

Results come out as mg/mL and mcg/mL together, because half of what you read uses one and half the other, and converting in your head is where errors creep in.

Syringe units, not just millilitres

A volume in millilitres is not what is written on the barrel. Pick U-100, 50-unit or 30-unit and the answer comes back in the units you will actually read.

Draws per vial

Knowing a vial yields eleven draws rather than twelve changes what you order. It is arithmetic, but it is arithmetic nobody does until they run short.

Frequently asked questions

How do I calculate concentration after reconstitution?
Divide the mass in the vial by the volume of diluent added. Ten milligrams into two millilitres gives 5 mg/mL, or 5,000 mcg/mL. The calculator does both conversions at once.
How do I convert millilitres to syringe units?
Multiply the volume in millilitres by the units per millilitre on your syringe. On a U-100 syringe, 0.05 mL is 5 units. The calculator asks which syringe you are using and answers in its units.
Does this tell me how much to use?
No. It reports arithmetic only. It does not recommend amounts, schedules or routes, and nothing it returns is guidance of any kind.
What is bacteriostatic water used for here?
It is one of the diluents used to reconstitute lyophilised material. The calculator does not care which diluent you enter — it works from the volume you tell it.

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