Lamictal.. titration

Hi to all
My daughter ( nonverbal, autism, 48)is almost finished with Zonisamide titration, 50 mg now for another week but having hard time with new Lamictal, at 100 now, her target dose till lab level done, but even tho she gets dose in am is having trouble sleeping, more so than usual which is common for autism but having behavior issues,
Just wondering if it is just a matter of adjusting? Zonisamide caused severe constipation leading to impaction, hospital stay so had to come off.. thank you.. a frustrated mom!