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c/reconstitution·submitted 4 days ago by u/dilara_szabo

foam means you shook it. do not shake it

Correctionbranch of 7 comments

foam means you shook it. do not shake it. I have gone back and forth on this for months. The lyophilised cake displaces a small volume, so the true concentration is very slightly lower than the arithmetic suggests. It is a fraction of a percent and it is dwarfed by fill tolerance. The arithmetic in full:…

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7 comments, started 3 days ago
u/santiago_ndiaye182 points·3 days ago·edited

Pushback on the syringe advice: a U-100 barrel reads units of volume. Calling them "doses" is how the confusion starts.

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u/dilara_szaboOP213 points·3 days ago

Correction: that gives 5 units, not what you have written. 30mg into 1mL is 30mg/mL and the division follows from there.

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u/ilias_cabrera101 points·2 days ago

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

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u/piotr_bruun62 points·2 days 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/emil_wojcik91 points·3 days ago

reconstituting at a round concentration makes every later dose easy

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u/wanjiru_varga76 points·2 days ago

reconstituting at a round concentration makes every later dose easy

emil_wojcik has the units point exactly right. They are a volume on the barrel and nothing else.

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u/tomas_kimani48 points·2 days ago

Agreed — units are volume. Once that lands, the rest of the arithmetic is one division.

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