A Screening Visit will be conducted to evaluate subject eligibility for enrollment into the study. Eligible subjects will return up to 21 days after the Screening Visit and begin Treatment Period 1. During Visit 2, eligible subjects will be randomized to receive either LCM 300 mg/day or CBZ-IR 600 mg/day. Subjects will be treated with their first randomized Antiepileptic Drug (AED) for 6 weeks (Titration Period [21 days] and Maintenance Period [21 days]). Subjects then complete a 28-day Taper/Washout Period, during which their first AED will be tapered over 4 days followed by a 24-day Washout Period, where subjects will receive no AED. Upon completion of the Taper/Washout Period, subjects will begin Treatment Period 2.The procedures and assessments for Treatment Period 1 will be repeated for Treatment Period 2 (with the same duration of treatment).