Absence Status Seizures During Successful Long-Term Clozapine Treatment of an Adolescent with Schizophrenia

This article reports the appearance of complex partial seizures during the course of successful use of the atypical neuroleptic clozapine in a 15 year old with neuroleptic-resistant schizophrenia. After 7 months of clozapine treatment, and 1 week after a gradual increase in dose to 550 mg, the adolescent began to develop periods of nausea and a "spacey feeling" that lasted for several minutes to hours at a time. A diagnosis of absence status was confirmed by electroencephalography (EEG). It was treated effectively by dose reduction (to 400 mg daily) without the use of anticonvulsant medications. A 3-year follow-up showed the generally sustained efficacy of this treatment, without recurrence of absence status seizures. This appears to be the first report of an absence seizure apparently associated with clozapine treatment. Published reports on 80 adolescents suggest an estimated prevalence of clozapineinduced seizures at about 4% (compared to 1-5% in adults, depending on dose), whereas 60% developed mild to marked EEG abnormalities. The current data on the safety and efficacy of clozapine for treating adolescents with schizophrenia remain preliminary. These data support the clinical recommendation that an EEG be obtained before adolescents are started on treatment with clozapine.