Dr.PainCLE said:Do it in two steps and it stops being confusing.
I am going to disagree with reconstituting low as a general rule. More diluent, more punctures, more in-use days at room temperature, and the stability trade-off is real. Precision is not the only variable being optimised.
The figures, for anyone assembling their own picture. Two things anyone can check: a state licence number for a 503A, and an FDA outsourcing-facility registration for a 503B. Both are publicly searchable, and a pharmacy unwilling to give you either has answered the question.
Dr.RaviCardio said:I am going to disagree with reconstituting low as a general rule.
Adding the part of the answer the thread has not reached. Resolution therefore closed the doors unevenly, and the asymmetry follows from the bulks lists. For 503B the shortage clause was the only route to these molecules, so that route shut completely. A 503A pharmacy can still argue a doorway via "component of an approved drug" — but only for the substance in the form present in the approved product, which is exactly where the base-versus-salt argument lives, and it does nothing about the copy restriction, which came back into force on resolution.
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Shop Reference StandardsA narrower follow-up, since the general answer is now clear:
How to check the arithmetic without trusting a website calculator, since three calculators gave me three answers?
Closing the loop on my own question.
My error was treating units as a mass. Once I wrote mg/ml on the vial in marker and worked in millilitres first, the two of us got the same answer.