@jaspal
I wouldn't switch seizure medicines as a preventative for side effects. All seizure medication's have significant potential side effects so you may just be trading some side effects for others or perhaps they'll be worse with another medication.
You also run the risk of increasing the possibility of breakthrough seizures, increased frequency, or intensity.
Also, I doubt any physician would be willing to go along with your plan. If you are consistently switching, your medication's driving may become an issue unless you live in a country where anyone with an epilepsy diagnosis has been banned from driving for live.
I'm not sure if you're taking an extended release medication but sometimes those help to decrease side effects but if the mood issues are bothering you, you probably should switch medication. Have you ever discussed the medication Lamictal with your physician?
Whatever medication you settle on, you should always make sure that your refills are from the same manufacturer.
How often were you having seizures?
One member here on connect stopped using anti-convulsant medication's and switched to a gluten-free diet which I believe decreased her seizures by 60% and also does yoga and meditation I believe. Her seizures have decreased significantly without the side effects of the seizure medication.
Take care,
Jake