As I understand it, it sounds like your pdoc is saying to split the Lamictal dose half and half into am/pm? At the higher dosage that is exactly what I did and it worked just fine. (It totally overwhelmed me taking it all at once - double vision etc). Sounds like he just suggested this? Give it a chance. It may well work for you. No need to worry about any concerns you have about lithium till you give this change a chance.