Linda, In my 15 years of experience with meds, the klonopin is the med that took time to build in the system while the ativan was more fast acting. Xanax is typically used for panic and anxiety but it takes time to find out what level is best. Keep an open line of communication with your psychiatrist and tell him/her how you are feeling and what these meds are or are not doing for you. Your psychiatrist's decision/advice that you up the Ativan until you get through this anxious period sounds like a wise decision since you are having panic breakthrough. I would just stick with the Ativan instead of incorporating the klonopin, too, so you will know what drug is doing what. Trust that your doctor knows what he is doing. I have a friend who is on both Ativan and klonopin, but he has such major agoraphobia he cannot leave his house. Good Luck, Linda.