I Have Rash That Is Spreading. I Have Been On

I have rash that is spreading. I have been on Lamotrigine with increasing dose for 5 months. The rash is beginning to be raised and slightly pustular. How do I stop the lamotrigine and resume Levateracetom?
I also have have a large number of colds since starting and well mild tremors in hands and mild difficulty with memory and lots of belching.