mirtazapine and zoloft. I am currently on a 50mg zoloft, this is my second week on zoloft. I have been taking restoril for sleep about a month and a half (15mg). Sometimes I have to take two to sleep. I am also on Xanon .25mg three times daily. I am being treated for prostatitis infection about six weeks now. I am wondering how safe mirtazapine is compared to restoril.