ZONISAMIDE SAFETY AND TOLERABILITY IN AN ADULT OUTPATIENT CLINIC POPULATION
Abstract number :
1.302
Submission category :
Year :
2003
Submission ID :
3665
Source :
www.aesnet.org
Presentation date :
12/6/2003 12:00:00 AM
Published date :
Dec 1, 2003, 06:00 AM
Authors :
Laura Hershkowitz, Kimberly Konieczki Northshore Clinical Associates, Erie, PA
Zonisamide is a broad-spectrum antiepilepsy drug (AED) with multiple mechanisms of action. In controlled clinical trials, 12% of zonisamide-treated patients discontinued the drug for adverse events. This retrospective chart review investigates the safety and tolerability of zonisamide in outpatients with a variety of seizure types.
Charts of patients from an outpatient practice who received zonisamide between January 2000 and April 2003 were reviewed for zonisamide dosage, use of other AEDs, length of time on zonisamide, adverse events, and reason for discontinuation of zonisamide (where applicable).
Charts for 95 patients with a variety of seizure types were reviewed. Mean patient age was 34.1 years (SD=16.1). Zonisamide dosages ranged from 100 to 800 mg/d. Patients received a mean of 1 other AED (SD=0.61). Most commonly used other AEDs included lamotrigine (n=21), phenytoin (n=15), and divalproex sodium (n=15). Patients received zonisamide for a mean of 58.1 weeks (SD=47.3). Twenty-one patients discontinued zonisamide without restarting it, 10 for adverse events, 9 for inefficacy/seizures, and 5 for other/unspecified reasons (some patients cited more than 1 reason for discontinuation). One additional patient elected to discontinue zonisamide but restarted the drug 2 days later. The most common adverse events were cognitive effects (n=4), weight loss (n=3), behavioral effects (n=2), gastrointestinal effects (n=2), and mood effects (n=2). Two additional patients reported weight loss, but this was not considered an adverse event, as the patients were overweight. One patient reported rash and discontinued zonisamide after 7 days. No patients reported kidney stones.
The tolerability of zonisamide and the adverse events reported in this outpatient seizure clinic population were remarkably similar to what was reported in controlled clinical trials. Notably, only 1 patient experienced rash, and no patients developed kidney stones while receiving zonisamide. Zonisamide was safe and well tolerated in this cohort of patients.
[Supported by: In part by Elan Pharmaceuticals, Inc.]