Just started Pristiq a week ago

I was on Zoloft for 4 months it was working very good the first two weeks then it stopped now I see a new psychiatrist who put me on Pristiq I'm now taking it but at the same time I'm taking 200 mg. 50mg of Pristiq the doctor told me to take 150 mg first week second week a hundred mg of Zoloft but when I tried that I had anxiety so I took both Zoloft and Pristiq now I'm feeling better I run out of Zoloft in a week and I'm going to continue to take Pristiq I could not take it and wait for it to take effect because my anxiety was so bad so I took them both at the same time what should I do now any advice the doctor told me to slowly go off Zoloft then take the Pristiq 150 mg I hope you understand this message

Hey ,

That’s the principle when changing from one antidepressant to another. They will decrease the dose of the old one then increase the dose for the new one. I was on Pristiq before for a few months but now I switched to lexapro. Pristiq is a SNRI that helps depression only, not anxiety . Is a newer version of Effexor. 

on pristiq 50 for 21 days has it started to work for you?