Abstracts

RATIONALE: Lamotrigine (LTG) is an antiepileptic drug approved as adjunctive treatment or monotherapy for generalized and partial onset seizures with or without secondary generalization. The purpose of this study was to review our clinical experience with LTG in the different epilepsies in an academic referral center.
METHODS: Patients with persistent seizures despite adequate trials of other AED(s) were started on LTG at a dose of 50 mg/d titrating up every two weeks to a maximum dose of 800 mg/d, except for patients on valproate who were started on 25 mg/d once every other day for two weeks, titrated up every two weeks to 200-300 mg/d. These patients were retrospectively followed for efficacy ([gt] 50% seizure reduction) and adverse effects.
RESULTS: Forty patients, who range in age from 18 to 78 years, were entered into the study. Seizures were classified as generalized (N=16) and complex partial with secondary generalization (N=24). Two patients had Lennox-Gastaut syndrome. Associated conditions included mental retardation, attention deficit disorder, cerebral palsy, depression, history of hypoxic and traumatic brain injury and a meningioma. Two patients had Vagal Nerve Stimulators. All patients were on one or two AED(s) when LTG was added. Mean duration of treatment at the last clinic visit was seven months. Ultimately, seven patients (17.5%) remained on monotherapy. Five out of these seven patients achieved 100% seizure control, one had greater than 80% reduction in seizures, while one patient had to stop treatment due to a late emerging rash . Efficacy of [gt]50% seizure control was reported in 60% of the patients including the two patients with Lennox-Gastaut syndrome. Rash led to discontinuation of the drug in one patient. Four patients had an increase in seizures after LTG was added and the medication was discontinued. Two patients experienced insomnia; in one this responded to dose reduction, and in the other to melatonin. Two patients experienced weight loss considered secondary to elimination of valproate.
CONCLUSIONS: LTG is well tolerated in the majority of patients (87.5%) in this varied population of adults with generalized and partial onset epilepsy. Approximately 60% had significant decrease in seizure severity and frequency. After previous exposure to multiple AED(s),17.5% of patients remain well controlled on LTG monotherapy. Improved quality of life secondary to weight loss, and elimination of tremor and menstrual irregularities were noted in those patients who could discontinue valproate.