Hi, i'm kinda new to this forum stuff; but, I have taken deprakote to try to get some type of control of my seizures. To be trueful - I hated taken it! Yes, weight gain was something to be dealt with.
The bigger question to answer isn't how much weight gained; but, if control of seizures has increased. This is a toughie -- it's like weighing the "positives" against the "negatives" to see which one has more. If the positives outweights the negatives, then seizures should be better controlled. This goes a long ways to helping us have better self-esteem. If gaining some weight is the price of controlling seizures - to me, it would be worth trying.
Unfortunately, deprakote didn't control any of my seizures, so my nuero has me on felbamate and keppra. So far it is better control; but, long ways to go.
Good luck to you! I really hope deprakote works for you.