round numbers
#reconstitution 2026-06-25
Thursday52 messages11 participantstimes are UTC
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you can absolutely just always use 2ml, and honestly most of us should
i have never once regretted using a rounder number and a slightly bigger volume
thats the vacuum
why does everyone say 2ml specifically and not 1ml
does it matter if i inject the bac water straight at the powder
quick one i swirl for about thirty seconds and then leave it. never had one fail to dissolve
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right so it foamed. is it ruined
it should be completely clear with no floaters. cloudy means stop, take that with a pinch of salt
i keep a spare vial of bac water in the fridge purely so i never rush the maths
benzyl alcohol is what makes it bacteriostatic. it is about 0.9% typically
10mg vial
+ 1.0ml -> 10.0 mg/ml 0.5mg = 5u 1mg = 10u
+ 2.0ml -> 5.0 mg/ml 0.5mg = 10u 1mg = 20u
+ 2.5ml -> 4.0 mg/ml 0.5mg = 12.5u (dont)
+ 5.0ml -> 2.0 mg/ml 0.5mg = 25u 1mg = 50upick the volume so your dose is a whole number of units. thats the entire trick
the last few units are a real loss. i accept it rather than tilting the vial and drawing air, ask me again in a month
i write the mg/ml on the vial with a sharpie the moment i reconstitute it
the vacuum will pull it in. let it. fighting it is how you get a face full of aerosol
if the powder is on the stopper, tap it down before you add anything. it will still dissolve either way, still working it out
bac water or sterile water for something im going into weekly for 3 weeks
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can i add more bac water later to a vial ive already reconstituted
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check your maths
5mg in 2ml gives 2.5mg/ml, 0.25mg is 10 units. good for a starting dose
anyone got a photo of what a properly dissolved vial looks like
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weighing the vial before you reconstitute is the only way to catch an underfill
if you draw up with a bigger pin and inject with a fresh one you lose a bit more to dead space, still working it out
15mg in 3ml is 5mg/ml. same numbers as 10 in 2, just more of it
10mg in 1ml is 10mg/ml, so 2.5mg is 25 units. thats the one i use
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label the vial
swirl it. do not shake it. the foam is denatured protein and you are not getting it back
does benzyl alcohol matter if im finishing the vial in one go
is the meniscus reading actually a real source of error or am i overthinking
Batch lookup B-0114: 9 independent reports on file, earliest 2026-03-21.
write the date on
while im here lyophilised powder is far more robust than people think. it is the solution that is fragile
swirl dont shake
if the maths gives you 13.7 units, change the volume. do not try to hit 13.7
while im here i use bac water even for a single-use vial because it stings less, which is not the reason it exists
yep 10 units
if you cannot read the mark confidently, your volume is too small. redo it at a lower concentration
right so do not add more bac water to an already reconstituted vial, you have lost track of the concentration
bac water
20mg in 2ml is 10mg/ml. 1mg is 10 units, 2mg is 20 units, easy
update from 24 months ago: switched to a single concentration and have not miscalculated since
a 3ml syringe for the diluent and a u100 for the dose is the setup most people here end up with
if you draw up with a bigger pin and inject with a fresh one you lose a bit more to dead space
i was wrong about this last year: it is fine to draw cold, it just stings more going in
gross powder mass is not net peptide. water and counterion are in that number
bacteriostatic water for anything multi-use. sterile water has no preservative in it at all
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dead space in a standard insulin syringe hub is small but it is not nothing over a month, i could be wrong
temperature of the diluent does not matter. how fast you push it in does
give it 5 minutes at room temperature before you decide it has not dissolved
one unit is 0.01ml. 100 units is 1ml. everything else in this channel follows from that, ill dig out the number
nobody here should be telling you a dose. we can check your arithmetic, thats a different thing, ill dig out the number
dead space
sorry to jump in weigh it first, from memory