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c/reconstitution·submitted 16 days ago by u/aurel_boateng

[PSA] let the alcohol swab dry before you puncture, that is the step everyone skips

PSAbranch of 8 comments

let the alcohol swab dry before you puncture, that is the step everyone skips, and I say this having got it wrong myself for long enough to be annoyed about it. The arithmetic in full: concentration is mass over volume, so 5mg into 1mL gives 5mg/mL. A U-100 syringe is graduated at 100 units per millilitre, so 0.75mg…

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8 comments, started 16 days ago
u/saskia_mwangi38 points·16 days 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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u/julia_erdogan-28 points·16 days ago

the number you write down is the number you will trust at 6am

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u/india_generic_g1 point·16 days ago

Correction: that gives 10 units, not what you have written. 5mg into 2mL is 2.5mg/mL and the division follows from there.

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u/ilias_cabrera11 points·16 days ago

Same. I got this wrong once, caught it because the units looked absurd, and have written on every vial since.

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u/karim_ilunga4 points·16 days ago

reconstituting at a round concentration makes every later dose easy

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u/ledger_modmod · vetting1 point·15 days ago

swirl, never shake

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u/declared_value_dv1 point·15 days ago

write the concentration on the vial in marker, that is the whole post

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u/lyophile_lou20 points·16 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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