I am 52 years old male and suffered from bleeding in basifrontal lobe nearly 4 years back. I was on on medication - Phenytoin 300 mg and Metapronolol Succinate 12.5 mg. After two and half years Phenytoin dosage was reduced to 200 mg and then after another six months to 100 mg. In the meantime I developed Cardiac Arrythemia (my one heartbeat is missing after every two heartbeats. My neurologist has stopped both the above medicines and told me that missing heartbeat may be side-effects of these two medicines. He has now prescribed Valparin Chrono 300. I am worried about this new medicines side-effects. Please advise !