Don't plug them. Works well with some drugs but not alprazolam. If you want to try to have them kick in a little bit quicker try taking them subllingually. Let them dissolve under your tounge. (They taste absolutley bitter and nasty, and try not to swallow).
This may help them kick in a little faster, but don't expect an IV rush of Xanax.
Oh yeah... don't try to IV Xanax either. Please, just don't.