SWIM has been taking xanax for anxiety for about 2 1/2 years. 1.5 a day. SWIM was recently given halcion so I took 1 .25. I feel absolutely nothing. Took another .25. Still nothing. What could be causing this. sWIM has seen people take halcion and could barely function and had amnesia. Could the fact that I take xanax be causing the halcion to not work. Not that they block each other, but due to xanax tolerance. TIA!