hi
your enquiry is tough to answer because you are asking whether you should go back to zyprexa, who can tell you except your pdoc. if you don't trust him search for another one since eventually you shall follow one. zyprexa has a strong stabilization effect like IL said but there are others too. The only question i can answer is that your lexapro won't help you for sure, on the contrary it may trigger all kinds of bad results, usually BP pts take along an AD an MS to cover it up.
What is wrongly known in the media is that SSRI helps in bipolar depression. I believe BP has nothing to do with seretonin rather it's the dopamine which affects it, this is why SSRI hurts not help. I came to this conclusionI after using stablon an SSRE which seems to decrease serotonin level (in contrast to ordinary SSRI), but seems to enhance dopamine.So serotonin has nothing to do with BP, but dopamine is strongly involved.
Again what people disregard is GABAergic agents at all. GABA (gamma-amino-butyric acid) is the most implicated in BP neurotransmitter. GABA deficiency is the main genetic marker of BP. So its deficiency results in extra excitability, up to mania. GABA is the main calming down neurotransmitter of the brain. There are MS including it like gabapentin (neurontin) has GABA in the beginning of its name.
in short you need a pdoc.
seroquel is good for sleep i take it myself and as an AP it covers well lexapro, but is it truly all what you need.? I feel your questions must be addressed to a pdoc and not to a forum, especially they are not specific and to me rather vague
good luck
Weight gain and temporary movement disorders can be a side effect of the medication you are taking. However, since its an anti-depressent if you have bipolar it may not be enought. If you started having moodswings after a traumatic brain injury the dosages and specifics of the medications you take would be different from standard bipolar. If you have never been diagnosed with a TBI and as to how that affected you see a neurologist. Zyprexa is an antipsychotic with mood stabilization properties but if you couldn't tolerate there are many other choices.