Topic summary

Second pass at: Choosing a concentration on purpose rather than by accident

Practice › Reconstitution worked example dead volume reconstitution

This is a generated summary. It shows the 7 most-liked posts from a topic of 49, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.

ni.kravchenkoTL230 Oct 2024 · edited#2

Bookmarking this. I will come back when I have something worth adding.

24 likes 21mo

bench_peakTL3Regular12 Nov 2024#12

e.almeida, post #3: I had written a reply contradicting the opening post and deleted it. Here is what survived. Reconstituting a multi-strength kit: if a kit contains 5 mg, 10 mg, 15 mg vials and you are reconstituting all of them, writing the concentration on each vial in permanent marker as you go is the single most useful thing you can do to avoid dose… Go to post

Coming back to post #8, because the follow-up matters more than the original answer.

Add the diluent down the side of the vial rather than directly onto the cake. It is slower and it avoids the foaming that makes people think something has gone wrong.

If anyone has run this properly I would rather read that than my own guess.

21 likes in reply to #3 20mo

n.dziedzicTL219 Nov 2024#19

r.sobczak, post #4: Worked example, since the arithmetic is the whole question. Five milligrams into one millilitre is 5 mg/mL. A 0.25 mg dose is 0.05 mL, which is five units on a U-100 syringe. Check that against your own numbers rather than taking mine. Go to post

I would rather this thread reach "we do not know" about Choosing a concentration than reach a confident answer that nobody can support when asked.

20 likes in reply to #4 20mo

f.petrovTL228 Nov 2024#28

A 10 mg vial reconstituted three different ways: 1 mL diluent gives 10 mg/mL, 2 mL gives 5 mg/mL, 4 mL gives roughly 2.5 mg/mL. The arithmetic is the same; the concentration determines which syringe graduations are legible.

I checked the source rather than the summary, and they differ.

28 likes 20mo

plateau_notesTL2Regular30 Nov 2024#31

That matches what I have seen, for whatever a single anecdote is worth.

21 likes 20mo

n.cardosoTL25 Dec 2024#36

o.lindgren, post #33: Choosing a concentration on purpose rather than by accident: starting with "I want to draw 0.5 mL per dose" and working backward to the required concentration is more efficient than picking a diluent volume and hoping the math works out. State your target volume, then the required concentration follows. Go to post

Reconstituting a multi-strength kit: if a kit contains 5 mg, 10 mg, 15 mg vials and you are reconstituting all of them, writing the concentration on each vial in permanent marker as you go is the single most useful thing you can do to avoid dose errors later.

30 likes in reply to #33 20mo

h.jansenTL28 Dec 2024#40

c.marchetti, post #24: Write the reconstitution date and the concentration on the vial. Not on a note, on the vial. Every account here of a dosing error involving the wrong concentration involves a vial with nothing written on it. That much is documented. The rest is how I have interpreted it. Go to post

This is the answer, and the reason it is the answer is the more useful part.

22 likes in reply to #24 20mo

Read the full topic (49 posts)

Moved from Dosing & titration by j.mwangi. Category placement is not obvious from outside and getting it wrong is expected. This topic will get better answers here. The move is recorded in the public log citing R7.

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