An evaluation of antiepileptic drug therapy in nursing facilities

To describe the prescribing and use of antiepileptic drug (AED) therapy in nursing facility residents.

A retrospective, multicenter drug use evaluation.

A total of 85 nursing facilities (average size, 119 beds) in five states.

1132 residents of the total 10,168 residents screened were prescribed at least one AED.

Demographic information, primary indication for AED, comorbid conditions, prescribing physician's specialty, concomitant medications, and AED dosage regimen information were collected. Laboratory tests obtained in the most recent 6 months and seizure occurrence and seizure-related diagnostic assessments made in the most recent 3 months were also recorded.

Of 1132 residents receiving AED therapy, 892 (78.8%) were prescribed AED therapy for a seizure-related diagnosis although 86% of seizure types were unspecified. Another 215 residents (19.0%) were prescribed AEDs for nonseizure diagnoses, and 25 (2.2%) had no indication for AED therapy. AEDs most frequently prescribed were phenytoin (56.8%), carbamazepine (23.0%), phenobarbital (15.6%), and valproic acid (13.1%). For residents with a seizure diagnosis, the most frequently prescribed monotherapy agents were phenytoin (52.0%), carbamazepine (12.2%), and phenobarbitol (7.1%). Almost 25% of residents with a seizure diagnosis took a combination of AEDs; more than 50% of all combinations included phenobarbital. About 9% of residents with a seizure diagnosis had one or more documented seizures during a 3-month review period.

Among the substantial percentage of residents treated with AEDs, the lack of diagnosis of seizure type has serious implications for the choice of AED therapy. Opportunities exist for prescribing physicians, consultant pharmacists, and nursing staff to improve the medical management of nursing facility residents with seizures and of others receiving AEDs.