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c/reconstitution·submitted 2 years ago by u/saskia_mwangi

[Discussion] mg/mL is doing more work than we give it credit for

Discussionbranch of 9 comments

Something I keep coming back to: mg/mL is doing more work than we give it credit for. Bacteriostatic water contains benzyl alcohol as a preservative, which is what makes repeated entry into the same vial reasonable. Plain sterile water has no preservative. If your calculation produces a fraction of a unit, the…

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9 comments, started 2 years ago
u/mateusz_achebe44 points·2 years ago

How many mg in the vial and how many mL are you adding?

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u/honest_syringe_202519 points·2 years ago

aim the stream at the glass wall, not at the cake

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u/sleep_apnea_sam7 points·2 years ago

the powder cake sits at the bottom, the volume you add is the volume that counts

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u/sofia_danquah10 points·2 years ago

Cosigning the round-number approach. Reconstituting to something awkward is how you end up drawing 27.5 units at six in the morning.

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u/saskia_rahimi16 points·2 years ago

reconstituting at a round concentration makes every later dose easy

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u/quiet_reader_9910 points·2 years ago

That only works if the fill weight is exactly the label weight, and it usually is not exactly anything.

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u/georgi_adebayo0 points·2 years ago

Yes, and the dead-space point is worth repeating: it is small, it is real, and it is the same for every draw.

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