Did you just start bupropion? It has a reputation for causing DP/DR and even panic attacks in people with anxious conditions, and I can back that up personally..

Ativan implies that you do.. but unfortunately (again from experience), inter-dose withdrawal with any benzo can cause mild to obscenely bad DP/DR.. (yeah, even clonazepam. half-lives don't mean much with some drugs because of where they deposit from plasma; fatty tissue for benzos, so even though it has a magical 'half life of 18-50 hours', it's only really pharmacologically active for 4-6 hours, or maybe 8 for a few people. Ativan's usually 2-4 hours for most people, about 2 for me. I don't even take free xanax.. after 45 minutes of feeling a little more OK, it's done and I feel horrible.. and that's got a 12 hour h/l.

I went off on a tangent, but I enjoy it.