Headache; nausea; diplopia; somnolence (in childn). Myoclonic seizures; problems in keeping balance, difficulties in coordinating movements or walking, tremor, paresthesia or muscle spasms, falling easily & getting bruises; troubles w/ memory, thinking or finding words, confusion; nystagmus, blurred vision; vertigo, feeling drunk; vomiting, dry mouth, constipation, indigestion, excessive gas in stomach or bowel, diarrhoea; decreased feeling or sensitivity, difficulty in articulating words, disturbance in attention; buzzing, ringing or whistling noise in ear; irritability, trouble sleeping, depression; sleepiness, tiredness or asthenia; itching, rash.