It depends, taking caffeine and alprazolam together does not make much sense, but it can reduce the jittery feeling of caffeine, for example. It may not have been mixed either, it is common to take benzos when coming down.
My point exactly
More people than should take stimulants to get going and sleeping pills to come down
They typically aren't taken together at literally the same time. It will be coke early in the night and then eventually xanax to get them to sleep because they are so wired.