I have switched between them. For me they were similar although I had one bad side effect with Ativan, I felt jerky.

I feel they are equal in dosages.

If you go up and down a lot it might be better to have a small steady dosage of Klonopin as a base, and add a little Xanax or Ativan when it is extra stressful.

If you're actually not just having increased anxiety but building tolerance, you need to down your benzo intake. Maybe not by much but a tad, for a few weeks, for your brain to recover, and then increase again, but not more than needed. This is mentally painful but better than building tolerance. Losing a benzo to tolerance is hell.

Also, even if antihistamines are not usually helpful on their own, with a benzo they can work, so maybe adding a tad Vistaril?

Talk to your doctor.