What should happen is a slow taper off the Ativan before switching to klonopin, especially since you've been on it for a long time. Just because the two drugs are in the same class doesn't mean switching from one to the other will eliminate withdrawal problems. Make sure, in my opinion, your doctor knows about this and how to do it to your satisfaction. As for klonopin being made for many years of use, nobody can predict that. You can reach tolerance on klonopin just as much as any other medication. No medication for anxiety or depression was made for long-term use -- they were all tested only for short term use as a bridge between crisis and therapy. They've become long-term in use because therapy often doesn't work, but that wasn't the intent when they were developed.
Klonopin is a long term med Ativan is not, you take a lot of it and it will stop working after a while that's why your having more anxiety, where klonopin does not do that it is made for many many years of using it.
I would try and take less if you can, I took .5 mg twice a day and it helped me, dr wanted me to take 1 mg 3 times a day but I knew that was to much, or you can take what he says and cut down as you start to feel more your self, wishing you luck on this
Your doctor should give you a plan for tapering off the ativan and on to the klonopin. If he does not, ask for one. Blessings - Blu