Does Lamictal cause memory loss???

I have been on the generic of Lamictal now for about 4 months. I had a very sharp memory in the past where I could memorize phone numbers just given to me and called later. I can't even remember the smallest things now and it is kinda scary for me. When I first started it, within a month I was doing great. I have seen more side effects like sleepiness and the memory loss in the last couple months. I take care of elderly people with 1st stage dementia and they remember more than I do. I went grocery shopping and left my groceries at the drive threw and didn't remember it until I got home and opened my trunk and they were missing!! It is getting bad.