There is no corelation between weight and epilepsy. However, weight gain may cause your medication to be out of whack. Weight gain may cause your medication to be the wrong dosage.

I advise talking to your doctor if you have gained significant weight and your medication is not effective.

Some anticonvulsants can cause fatigue, if you get it alot your weight will increase due to lack of exercise, to prevent weight gain try to keep more active.

There are medications that have side effects of Wieght gain

It’s not Epilepsy that causes weight gain . Although there are AED side Effects , that can cause weight gains and even weight loss .

Then there is the type of foods and exercising we do or not do that can causes weight gain or weight loss

I don't think the weight is related to the condition. It is from the medication a person takes and the side effects it has.