My Mother Has Been Started On Lamotrigine (started Initial Dosing

My mother has been started on Lamotrigine (started initial dosing 8--26-2018 in an effort to transition from Keppra to Lamotrigine. She just woke, could hardly walk, very disoriented, urinated on the floor etc... this is a significant change from her current rehab baseline. Could this be related to this medication? No s/s of rash or swelling.