There's probably not much that you can say.
Did your employer require you to fill out an application? I mean, because
I know you said that you had already been working for them through an
agency... but still, most places still would require you to fill out an official
On the application, it should have asked why you left your last job.
Right then is when you probably should have explained what happened.
Or rather, that is what your HR/boss/whatever, is going to say when
you use the excuse "well, I didn't know that you all needed to know
Or did they NOT have you fill out an application. If that is the case,
then you may indeed be able to say, look, no one asked me about
this, this never came up... didn't see any reason to mention it.
And then there's the whole issue of you not being able to give
narcotics because of your probation. Your employer may decide
to terminate you for that reason alone, if your job does entail
having to give a lot of narcotics. You work GYN, I would
assume that it does.
I hope things work out for you. If you are let go... there
are places out there that will still hire you in spite of your
probation, but please be transparent about everything that
has happened. Good luck.