My first tought was poop-out, but that doesn't happen with bupropion, only with SSRIs, right? You shouldn't stop and start again the same antidepressant (and, to a lesser extent, antidepressants in the same family, or that target the same neurotransmitter), this will build resistance.
With SSRIs, poop-out tends to be resistance at any dose, not tolerance. I've had poop-out from placebo (WTF?) and larger doses don't work there either.
A week is a bit short for a test, but bupropion is unusually fast so that's a decent test. Why are you trying to correct for the placebo effect at all? Improvement from placebo is real and desirable, and there's probably a feedback loop between placebo- and drug-related improvement that helps even further.
How many antidepressants have you tried? You might just be on the wrong one. How large is your dose? If you're at 300mg/day trying going up to 450 is possible, though I'm not very optimistic. Does your depression have a seasonal pattern at all, and if so could the weather be responsible for the mood drop? You seem oddly trusting in self-experiment and advice from strangers; why are you seeking recommendations besides your psychiatrist's? Cost?
Disclaimer: I'm a nutjob who reads Crazy Meds and Neuroskeptic, not a psychiatrist.
Yeah, poop-out could be the culprit. However, this would also suggest that the positive effects were mainly placebo because, as you mention in your second comment, the most reasonable account of poop-out is that the placebo effect wears off.
I was correcting for placebo cause I wanted to try lots of different antidepressants and other drugs and see which "really" work. But I guess you're right; the placebo effect is pretty amazing and one shouldn't risk eliminating it by over-zealous self-experimentation.
I haven't tried any other antidepressants since I f...
Admitting to being wrong isn't easy, but it's something we want to encourage.
So ... were you convinced by someone's arguments lately? Did you realize a heated disagreement was actually a misunderstanding? Here's the place to talk about it!