When t comes to meds, everybody responds differently. However: Zoloft did nothing for me. Yes, I have been on an SSRI and lithium at the same time. It was quite a while ago, and I don't remember what happened. I believe the latest thinking is that bipolar depression is different from unipolar depression and that SSRIs are nor a good idea for people with BP. They can kick you up into mania.
i was on efexor and lithium for a while...eveything comes with a warning but its what we gotta do...
Antidepressants being paired with a mood stabilizer such as lithium is pretty common as an antidepressant without a mood stabilizer can lead to mania. I would trust your psychiatrist in this as he will watch you closely for this syndrome, and if there was any serious concern over mixing the two, the pharmacist would've been obligated to question this combination.