#reconstitution 2026-06-13

swirl dont shake

Reminder for yara_yields: dose day is today. Set 7 days ago.

how much do i lose to dead space with a 31G pin
give it 6 minutes at room temperature before you decide it has not dissolved

one unit is 0.01ml

my rule is one concentration for everything so i never have to think about it at 7am

anyone worked out a recon volume that puts 15mg on a round unit mark

thats the vacuum

round numbers

do not add more bac water to an already reconstituted vial, you have lost track of the concentration, anyway

i have never once regretted using a rounder number and a slightly bigger volume

my 10mg vial weighed 11.4g on the jewellery scale, is that wrong

sanity check my maths before i pin myself with something stupid

clear or bin it

i write the mg/ml on the vial with a sharpie the moment i reconstitute it, n of 1 obviously

why does everyone say 2ml specifically and not 1ml

update on the earlier thing weighing the vial before you reconstitute is the only way to catch an underfill

quick one the vacuum will pull it in. let it. fighting it is how you get a face full of aerosol

the jewellery scale is a good habit but calibrate it, they drift badly, anyway

weigh it first

does temperature of the bac water matter at all

write the date on

aim the diluent at the glass wall, not at the powder. it goes in gentler

if the maths gives you 13.7 units, change the volume. do not try to hit 13.7

if the powder is on the stopper, tap it down before you add anything. it will still dissolve either way

you can absolutely just always use 2ml, and honestly most of us should

what do you do with the last 20 units when you cant draw them cleanly

read it at eye level

my vial pulled the water in on its own, is that the vacuum or did i do something

lyophilised powder is far more robust than people think. it is the solution that is fragile, ill dig out the number

5mg in 2ml gives 2.5mg/ml, 0.25mg is 10 units. good for a starting dose

coming back after 5 months, has the pinned recon volume advice changed

how long after reconstituting before its actually dissolved

the last few units are a real loss. i accept it rather than tilting the vial and drawing air

if you draw up with a bigger pin and inject with a fresh one you lose a bit more to dead space, someone check my working

ok so update from 17 months ago: switched to a single concentration and have not miscalculated since

slightly off topic but gross powder mass is not net peptide. water and counterion are in that number

nope, redo it

thats 5mg/ml

do i swirl for a specific length of time or just until its clear

do you let it come to room temp before drawing or draw it cold

i keep a spare vial of bac water in the fridge purely so i never rush the maths

dead space in a standard insulin syringe hub is small but it is not nothing over a month, anyway

i swirl for about thirty seconds and then leave it. never had one fail to dissolve

is it normal for the cake to look slightly collapsed on one side

10mg in 1ml is 10mg/ml, so 2.5mg is 25 units. thats the one i use

not sterile water

check your maths

give it 5 minutes at room temperature before you decide it has not dissolved, still working it out

a 3ml syringe for the diluent and a u100 for the dose is the setup most people here end up with
do not add more bac water to an already reconstituted vial, you have lost track of the concentration

benzyl alcohol is what makes it bacteriostatic. it is about 0.9% typically, i think

20mg in 2ml is 10mg/ml. 1mg is 10 units, 2mg is 20 units, easy

i was wrong about this last year: it is fine to draw cold, it just stings more going in

yep 10 units

it should be completely clear with no floaters. cloudy means stop