This probably doesn't count as it's not prescription, and probably not even classified as an anti-depressant. But, I thought I'd interject my experience anyway - for what it's worth.
I took Saint John's Wort for years ... only weaned myself recently from it when I decided to try for a baby.
In terms of feeling different, I don't know if my experience was unique, but for me it was like night and day. After 6 weeks, the "mindless, numb, indifferent, bleak hole of despair" - sorry, it's the only way I can describe it - just disappeared. Just like that, it was gone. And I felt like myself again. I had no other side effects but that.
I did take SJW in conjunction with doing other things, i.e. exercise, eating well, journaling, etc. But, I had been doing all those things prior to SJW and they hadn't helped. For me, it was like a miracle.