I have been taking lamtrigine for years and haven't had any problems with weight gain. If you look on the website for lamtrigine it says it doesn't cause weight gain or loss. But people are different and meds react different to different people.

I have gained so much weight and recently started taking Ozempic for my type 2 diabetes and so far the hungar has subsized..praying it off sets the weight gain and I brought an elliptical machine to work out on and some hand held weights

They never took me off of it so I don't know, they just keep adding more and more pills for me to take.

5% of people taking it gain weight. And unfortunately I'm one of them.