Hi Raghu, Thanks for writing in to Healthcare Magic! The Zen contains the drug Carbamazepine which has got many side effects like dizziness, drowsiness, ataxia; dry mouth, abdominal pain, nausea, vomiting, anorexia; leucopenia, proteinuria, renal failure, heart failure and the HYPONATREMIA. Potentially Fatal: Agranulocytosis, aplastic anaemia, hepatic failure, severe exfoliative dermatitis and Stevens-Johnson syndrome. All reactions do not occur in each patients but depends on patient-drug interaction. I think you had enough treatment duration with seizure free interval and you should taper off the drug in supervision of a good physician. I hope you would maintain without drug now. If you have any further query please let me know I would try to answer it for you. Wish you a great health!