I have been taking 30 mg pexeva for 5 years for gad and severe panic attacks. Even though I was content with the meds helping , lately I have been having severe panic attacks. My dr suggested taking 15mg pexeva (breaking tab in half) and adding Pristiq 25mg for 1 month before making the switch to 50mg Pristiq. I am on day 4 and I feel alittle light headed and nauseas. Any advise for me, I get nervous from this feeling. Dr also gave me klonopin that I take 0.5 twice a day. It helps but when I experience the nausea it's all over for me. Please help ?