Are There Any Side Effects With Prolonged Usage Of Encorate Chrono?

I am on encorate chrono 500 1+1 from past 7 years it has controlled my seizures which I used to get once a year .
I have not got an attack from nearly seven years.Are there any side effects with prolonged usage of encorate chrono 500.

I am in India and I visit neurologist regularly.Please answer my question then I will pay if I am satisfied.