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c/reconstitution·submitted 3 days ago by u/cesar_ivaturi

mg ÷ mL, that is the whole formula, why did i find this hard

Discussionbranch of 7 comments

mg ÷ mL, that is the whole formula, why did i find this hard, which sounds obvious until you try to state the evidence for it. Started reconstituting everything to a round concentration and the six-in-the-morning error rate went to zero. The whole calculation, once, with real numbers. You have a 30mg vial. You add…

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7 comments, started 2 days ago
u/yusuf_nakamura-7 points·2 days ago

The arithmetic in full: concentration is mass over volume, so 20mg into 2mL gives 10mg/mL. A U-100 syringe is graduated at 100 units per millilitre, so 1.5mg is 1.5 divided by 10 millilitres, which is 15 units.

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[deleted]1 point·2 days ago

[deleted]

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u/RetaAndRegret21 point·2 days ago

The arithmetic in full: concentration is mass over volume, so 20mg into 2mL gives 10mg/mL.

Right, and the arithmetic behind it: 5mg in 2mL is 2.5mg/mL, so 0.25mg is 10 units.

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u/vial_math_veraMOD1 point·2 days ago

Reminder: this board does maths, not dosing. Nobody here tells another member what amount to take.

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u/cesar_ivaturiOP1 point·2 days ago

What concentration did you actually reconstitute at, rather than what did you intend to?

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u/emeka_delgado1 point·2 days ago

I would not round that figure. At 5mg/mL a rounding error of two units is a real fraction of the intended amount.

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u/cesar_ivaturiOP1 point·1 days ago

Wrote the date on the vial as well as the concentration after losing track of which one was opened first.

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