Suggest Treatment For The Side Effects Of Lamotrigine

I take lamotrigine 100 mg and bupropion 100 mg both once a day. I am concerned about the side effects of the lamotrigine (of which there are many, but particularly the itching, which plagues me a lot when I take it) I need to have enough antidepressants in my system to control my depression, but I'm wondering if there are any alternative drugs to take in place of the lamotrigine or if I should just consider increasing the dosage of the bupropion and eliminate the lamotrigine altogether from my medications.
In addition, I have extreme sleep issues, and take both trazadone 50 mg and quetiapine 100 mg nightly to combat my chronic insomnia.
I've had a liver transplant, and therefore have to take 2 immuno suppressant medications (prograf 7 mg and cellcept 500 mg) daily so it is important for that to be noted before any alternative suggestions/changes should be made to my medication regimen.
Thank you so much for your assistance in this matter.