Reconstitution in one worked example

Reconstitution math trips up more people than any other part of peptide handling, and it is almost always the same confusion between weight, volume and syringe units. One worked example clears most of it up.

Say you have a 5 mg vial of BPC-157 and you add 2 mL of bacteriostatic water. Concentration is total peptide divided by water, so 5 mg divided by 2 mL is 2.5 mg per mL.

Your target is 250 mcg, which is 0.25 mg, since 1 mg is 1,000 mcg. Dose volume is target divided by concentration, so 0.25 mg divided by 2.5 mg per mL is 0.10 mL.

Now convert to syringe units. On a U-100 syringe, 100 units is 1 mL, so multiplying the volume by 100 gives 10 units, which is the 10 mark on the barrel. This is unit math for reading the research, not a step to carry out.

The same three steps, concentration, then volume, then units, work for any compound and vial. If you would rather not do it by hand, the calculator runs all three.

One note on units: syringe units are volume marks, not international units and not a dose in milligrams. Twenty units is always 0.20 mL, whatever is dissolved in it.