You probably can, but if your new doc gives you a script for the exact quantity and dosage for the one you want to fill, you will not be able to fill the new docs one until after the other script is finished or at least 4 days from it finished(I can fill schedule 2 scripts 4 days early).

But if the new doc gives you a script of the same med but with either a different quantity and/or strength, then legally you can. However it is legally up to the pharmacists discretion to fill or not if you should have pills from the most recent script.

However, your new doc will more than likely look you up on the nationwide PDMP database to see your pasts scripts. Same goes with the pharmacy, they’re suppose to look you up on there as well before filling any scheduled meds.