So if your doctor is looking at possibly having you trial any other psych med? First step will be to taper you off this one, completely.
@Tim W. - I just wanted to add a thing to friday's post. Since Belviq is relatively new, most data sets have not developed beyond testing how the drug affects people after being used regularly for a year or less. You've been on it 3.5 years, and that (unfortunately) means that you're in the no-mans land of, no-one knows how the drug behaves.
It does have psychiatric effects, as friday pointed out. They are not well-understood. It's very possible that you will need to weather a discontinuation period, in order to just get off of the stuff. Talk with your doctor about what your best options are for getting off the belviq, how to schedule that into your life, what drugs you might be able to use to mitigate some of the discontinuation symptoms, and how to give yourself the best shot at keeping track of all of that, so that you can get yourself back to the 75% better that you have been able to be.
Some drugs are odd in a particular side effect: you cannot come off of them and then use them again. They will have a tendency to not work. I only know a very little about this, and certainly there's no-one who could say with certainty that belviq is one of those. It sounds like your experience, though, might be indicating this. If you find that you don't come back up to your previous steady state in another week or so, after giving your dose the bump back up, that could be the reason why. In other words, it's possible.
I'm so sorry. This kind of stuff is just so hard, annoying, frustrating....all those kinds of words. Shitty, really.