Pristiq is a very different drug from most of the others you've tried. It's an antidepressant while the others are antipsychotics used in the treatment of bipolar conditions and schizophrenia. Abilify works differently from the other antipsychotics, and is supposed to cause far less weight gain. It can also be used for major depression but only in combination with antidepressants.

So far as I know, the others you mention can have the side effect of weight gain because of the specific ways they affect body chemistry. They also tend to have a sedating effect that helps control mania and agitation. It sounds like your insurance company has a list of drugs approved for certain conditions - and those always tend to be generics because they are so much cheaper than the new ones. Many insurance plans, though, allow you to use drugs not on their list but make you pay a much higher copay. That's worth checking out.

Research seems to be showing that the newer antipsychotics, called atypicals, are no more effective than the old ones. Controlling side effects is probably the main issue, and you'll need to talk with a psychiatrist who knows more about these drugs than a primary care physician would.

John