I believe Risperdal definitely has a weighty side effect.
I'm bipolar and currently taking wellbutrin, effexor, lithium, provigil, valium PRN, and armour thyroid. The lithium is the weighty med here, but I'm not on a big dose. And believe it or not, I just got off 2 other meds (Geodon & Lamictal--not weighty meds). I tend to be medication resistant and have a high tolerance.
What one of my bipolar books suggests for self management is a healthy diet. They suggest no refined sugar, white flour, white pasta, etc. It helps keep your mood stable by keeping your blood sugar level stable. I found it has also decreased my appetite and stopped my binging.
What kicks my butt is the fatigue part of the depression mood swing. I am not exercising although I want to. For my weight and mental health.
You can do it. Good luck.

Amy