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c/reconstitution·submitted 7 months ago by u/viktor_erdogan

[Question] how do you actually verify dead space

Questionbranch of 18 comments

Week 9 update. 40kg down from the start, muscle cramps basically gone since about week 49. Things that worked: consistency, protein at breakfast, walking more than I want to. Things that did not: everything I bought on the internet to help with muscle cramps. The part that surprised me is how much of this is admin.…

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18 comments, started 7 months ago
u/bac_water_banditMOD121 points·7 months ago

Flair changed to match the content. Read the sidebar before posting next time and we are square.

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u/lyophile_lou-5 points·7 months ago

Spent 17 weeks confused about concentration math until someone showed me the table. 10mg, 2mL, concentration is 10/2.

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u/tuva_kirchner95 points·7 months ago·edited

Is that 10mg vial or 11mg?

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u/rosa_mensah49 points·7 months ago

u-100 syringe, not u-40, or your math is off by factor of 15

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u/viktor_erdoganOP93 points·7 months ago

The single most useful thing I did was write the concentration on the vial. Stopped all the confusion after that.

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u/rasmus_kuipers59 points·7 months ago

Show the arithmetic. Where did the units come from?

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u/bac_water_banditreconstitution20 points·7 months ago

bacteriostatic and sterile water are not interchangeable, do not use them that way

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u/santiago_ndiaye70 points·7 months ago

Disagree but this is the good kind of wrong — it is specific enough to be checked.

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u/georgi_adebayo44 points·7 months ago

Cosigning. The concentration on the vial in marker is load-bearing.

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u/erez_perrin16 points·7 months ago

dead space is real and the syringe matters

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u/hub_opssite staff75 points·7 months ago

The single most useful thing I did was write the concentration on the vial.

Disagree on that part. 98.9% and 99.0% on the same vial is normal.

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u/erez_perrin50 points·7 months ago

stopper coring on the 24th draw because you keep using the same entry point. rotate.

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u/hedda_adeyemi14 points·7 months ago·edited

stopper coring on the 24th draw because you keep using the same entry point.

Disagree on that part. 99.2% and 97.6% on the same vial is normal.

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u/viktor_erdoganOP47 points·7 months ago

20mg vial, 2mL water, concentration is 20/2 — write it on the vial afterwards

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u/georgi_adebayo12 points·7 months ago

dead space is real and the syringe matters

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u/rosa_mensah5 points·7 months ago

Are you using a u-100 or u-40 syringe? That changes everything.

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u/andres_sorensen16 points·7 months ago

the concentration on the vial in marker is the most important step

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u/sleep_apnea_sam13 points·7 months ago·edited

Yeah, showing the arithmetic is the fastest way for someone to spot the error.

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About c/reconstitution

The arithmetic and the technique. Bacteriostatic versus sterile water, reconstitution volume as a concentration choice, converting mg/mL into insulin-syringe units, dead space, swirl-not-shake, stopper coring, and how long a reconstituted vial is actually good for. Math errors get corrected fast and politely.

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