Can you od from mixing 4mg xanax (alprazolam) with 2000mg gabapentin?

Overdose.: Yes this is an "overdose" to someone who had never taken either of these meds. But if this person has been taking both these meds in these doses it may not be too much. In general these meds are pretty safe if there are no other co-ingestions. Marked drowsiness and amnesia are to be expected, but death would not be common with this combination.

Yes: The 2000 mg of gabapentin is already over the maximum dose for this medicine. So by one definition, this is already an overdose. If you're asking if this combination could kill you, I'd have to says "yes it might" since this type of combination can slow breathing. The combined effects, depending you your size and metabolism and tolerance for these meds, could conceivably stop your breathing.