Hi and welcome to PC. I have BP2 and have been on Lamictal for a while with great results. It is considered a weight neutral medication. I'm not sure about the Topomax. I think since you were able to already take off 15 lbs. that you will be able to take off the rest. Exercise and a healthy diet are very important for the depression as well as your weight. This is a great place to get and give support.