This isnt a what should I take, its more of a "What if I took" Ive taken Zoloft (sertraline) for 8 years. What could POSSIBLY go wrong if I took Ayahuasca?
What would ACTUALLY happen is that you would experience an adverse drug interaction and be very uncomfortable. What could POSSIBLY happen is that you would die a horribly unpleasant death. Please don't mix SSRIs and MAOIs, this is a combination well known for causing potentially lethal amounts of serotonin overload.
Zoloft is a Serotonin Reuptake Inhibitor, so any free serotonin in your synapses wouldn't be reabsorbed. Combined with the MAO-a inhibition by the harmala alkaloids in the ayahuasca brew this would lead to an overload of serotonin in your brain (as a MAO-inhibitor breaks down excess serotonin)
(I'm a layman so keep that in mind but if I'm wrong another member here will correct me)
You would from the top of my head experience confusion, overheating, probably some spasms and I guess your heart will do unfunny stuff too. And then you die. (well probably not necessarily but the main point here is ayahuasca + Zoloft is a no-go)
I'd love to hear an elaborated explanation of what happens in the case of serotonin syndrom by a more knowledgeable member.