The tolerability of lamotrigine in elderly patients with epilepsy

Objective: To determine the tolerability of lamotrigine in elderly patients with epilepsy. Design: Pooled data from 13 lamotrigine clinical trials. Setting: Multicentre clinical trials conducted in primary care and neurolog y practices. Participants: 208 elderly patients (aged greater than or equal to 65 years) were identified: 146 lamotrigine-treated patients, 53 carbamazepine-treate d patients and 9 phenytoin-treated patients. Interventions: Extent of exposure, incidence of drug-related adverse events , serious adverse events and study withdrawals were examined. Results: The median duration of exposure for lamotrigine monotherapy and ad d-on therapy was 24.1 and 47.4 weeks, respectively. The median daily dosage of lamotrigine was 100 mg for monotherapy (range 75 to 500 mg) and 300 mg for add-on therapy (range 25 to 700 mg). Overall, the incidence of drug-rel ated adverse events was lower for lamotrigine than comparator drugs: 49% (7 2/146) for lamotrigine compared with 72% (38/53) for carbamazepine (p = 0.0 06), and 89% (8/9) for phenytoin (p = 0.035) although patient numbers in ea ch treatment group were not comparable, Patients receiving lamotrigine repo rted incidences of somnolence (p = 0.012), rash (p = 0.034), and headache ( nonsignificant) that were one-half the incidence reported with carbamazepin e monotherapy. Rash was the most common reason for study withdrawal: 4% (6/ 146) lamotrigine, 17% (9/53) carbamazepine and 0% phenytoin. Seven (5%, 7/1 46) lamotrigine-treated patients, 4 (8%, 4/53) carbamazepine-treated patien ts and 1 (11%, 1/9) phenytoin-treated patient experienced drug-related seri ous adverse events. Conclusion: Lamotrigine, used in the currently prescribed adult dosage regi men, was well tolerated in elderly patients with epilepsy.