I had extreme nausea on a very low dose of abilify (aripiprazole) & had to discontinue use? would buspar have a similar side effect? also does it cause weight gain

Different drugs: Abilify (aripiprazole) and Buspar are very different medications, Abilify (aripiprazole) is an antipsychotic and Buspar antidepressant. One should not be substituted for the other and you need to ask a doctor what you really need. Buspar does not cause weight gain usually.

Not likely: Buspar and Abilify (aripiprazole) affect very different brain systems and have different uses. Each has its own side effect profile. (the one cannot be substituted for the other.).