My psychiatrist recently put me on both, but only with the goal of switching me from one to the other (Lexapro to Zoloft). She called referred to it as 'crossing over' in that I was to systematically go from 20mg Lex down to 15mg and add 25mg of Zoloft for the first week. Then, 15mg Lex down to 10mg and increase Zoloft by 25mg to now 50mg. Her goal was to get me to 75mg Zoloft or 100mg, but I opted to remain at 50mg and will plan to drop to 25 or even 0mg for the summer. I am treated for SAD and some dysthymia.