When a prescription is written per kilogram of body weight, the total amount changes with the patient. This tool does that conversion and, if you enter how the vial was mixed, shows how much liquid to draw. It never proposes a dose: the per-kilogram figure has to come from the prescriber.
Total dose = body weight in kilograms × prescribed dose per kilogram. Pounds are converted at 0.45359 kg per lb. If you enter the vial contents and the diluent volume, the tool divides the vial's micrograms by the millilitres added to get the concentration, then divides the total dose by that concentration to get the volume. On a U-100 insulin syringe, 1 mL equals 100 units, so the volume is multiplied by 100.
Suppose a prescription reads 2 mcg/kg and the patient weighs 165 lb. 165 × 0.45359 = 74.8 kg, and 74.8 × 2 = 149.7 mcg. If the pharmacy mixed a 5 mg vial with 2 mL, the concentration is 5,000 ÷ 2 = 2,500 mcg/mL, so the volume is 149.7 ÷ 2,500 = 0.060 mL, or 6.0 units on a U-100 syringe. The numbers here are illustrative, not a recommendation.
Earlier versions of this page listed per-kilogram ranges for unapproved peptides. Those figures were extrapolated from animal studies and seller protocols, not from human trials, so we removed them. For approved medicines, the per-kilogram dose is in the prescribing information and is set by the prescriber. See our Peptide Guide for each compound's regulatory status and evidence.
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