I was switched by my doctor, a psychiatrist, to Prestiq from Effexor, and I have noticed a decrease in anxiety.  However around the same time as I began the prescription for Prestiq, my pharmacist inadvertently gave me a prescription for Sertraline HCL along with it.  I was already on Lexapro in addition to Effexor so I discontinued the Lexapro on my own thinking that was probably a duplication of Sertraline (Zoloft) which my doctor must have authorized.  My doctor wasn't very happy with the pharmaceutical error, but decided that if it seemed to be working for me he would continue with it.  So now I'm on the Zoloft and Prestiq which so far has been satisfactory.  (Sounds quite confusing!)