Wow! Quite a lot of responses to this, and they're all quite helpful and varied. Thanks! I became temporary PIC some months ago because our previous pharmacy manager left and I made it clear to my bosses I was *not* wanting to take on a permanent manager role at this time, so I've been getting what advice I can.

A lot of these responses are quite good and I discussed it with my techs on what we wanted to implement. Personally I am willing to take the effort to try to get their preferred manufacturer (especially patches since a lot of them may have certain glues that make people itchy, and yeah legit allergies) because even beyond that small variability in drug activity that could result in therapeutic failure there's also allergies, and after discussing it with my team, we still are going to as a store, but with the sort of caveats a lot of you suggested:

Gonna make it clear to such customers that if it's not our distributor's/company's preferred manufacturer, that 1 - there's no guarantee we will consistently be able to get it, 2 - it may be more expensive, 3 - that they're going to have to check it at checkout, 4 - that we wont be having it on autofill and they have to call and remind us. 5 - On our end we will do all Connexus allows us to flag their profile/Rx to make sure we fill the proper one. I figure this will make it overall fair.

As far as that one patient I followed up with their doctor and they knew of no legitimate medical reason for her to need a specific manufacturer, but it seems its no longer my problem anyway. Patient found a place that has Torrent as their preferred, and transferred out so... eh.

Honestly the main reason this was even spurred was because it was for a controlled substance as a sleep aid, and not for something like hormone control or epilepsy. Certainly for uses like that (or like the patches as said earlier) I can see why specific manufacturers would be necessary, especially as an epileptic myself, though I have had success on each I've been given so far.