I have been on alprazolam for 20 years. I did not build a tolerance to it. I went from 1 or 2, 0.5 mg a day for 15 years, to 1/2 a tablet every three days, for 5 years. Anyway, I have been itching all over with no rash for about a week. It may be allergies but I was just wondering if anyone ever experienced this before?