It is VERY hard to manage bipolarity without meds. I wouldn't advise it, unless you had a really good therapist that you could call every time you got mad, upset, or otherwise... at any time of the day.

It also depends on how severe your bipolar is. You have to gauge that yourself. If you have good self control, then you may be able to go without meds, but being bipolar, I doubt that you do. I recommend Lamictal for bipolar. It's what I take. It calms me down without any weird side-effects.