Hypohidrosis-related symptoms in pediatric epileptic patients with topiramate

Background: Topiramate is one of the most commonly prescribed newer antiepileptic drugs. However, we have encountered quite a few cases of pediatric epileptic patients on topiramate complaining about the symptoms related to hypohidrosis. The aim of this study was to determine the incidence and define the clinical characteristics of hypohidrosis-related symptoms with topiramate in pediatric patients. Methods: Data was collected prospectively on 264 patients diagnosed as having epilepsy and treated with topiramate at the Department of Pediatrics, Chonbuk National University Hospital between July 2004 and July 2006. The data were collected by direct interview after at least 3 months had elapsed from the initiation of the medication. Results: The study group was composed of 70 boys and 81 girls, with a mean age of 33.1 +/- 43.2 months. The mean duration of topiramate treatment was 13.4 +/- 15.0 months; 52 patients (34.4%) were treated with topiramate only and 99 patients (65.6%) were on polytherapy including topiramate; 59 out of 151 patients (39.1%) experienced hypohidrosis-related symptoms: such as facial flushing, lethargy, itching sensation, irritability with hyperthermia, heat sensation or heat intolerance. However, there were no patients complaining of hypohidrosis-related symptoms among those who were taking antiepileptic drugs other than topiramate. Conclusions: Our results suggest that topiramate induces hypohidrosis-related symptoms more often than we expected, especially in pediatric patients. We recommend that pediatric epileptic patients taking topiramate should be warned to avoid hot and humid environments, especially during the hot summer season.