How Long Should Tegrital-200mg Be Taken For Epilepsy?

Hello!I had epilepsy during 2000. I was advised by Doctor Tegrital 200mg. After that I didn't had any seizer for three years.Then I became careless and became irregular in taking madecine.I had another seizer in 2005.I visited the doctor,he recommended Oxinate-300mg,but it was not available at all the places.I consulted another doctor he recomended to continue Tegrital-200mg.After that I became regular in taking medicine.5.5 years gone,since then I didn't had any seizure attack .Can you please tell how long should I continue it or shall I stop taking it now.