Pediatric Case Report of Topiramate Toxicity

Abstract

Background. Topiramate is an FDA-approved second generation antiepileptic drug with actions on voltage-dependent sodium and calcium channels and GABA and excitatory amino acid receptors. There has only been one prior pediatric case report of topiramate toxicity. We report a 33-month-old girl with persisting neurologic symptoms after acute ingestion of topiramate. Case Report. A 33-month-old girl was found at her sitter'shouse with a bottle of topiramate (100-mg tablets). She presented to the emergency department 3 days post-ingestion. The child appeared confused and was only able to crawl. At one point, she looked directly at mother and asked, ‘‘Where is my mommy?” She had visual hallucinations and screamed while pointing to objects on the wall. Neurologic exam was notable for the slurred speech and severe ataxia. All laboratory testing, urine chemical dependency screen, CSF, chest X-ray, head CT, and EEG showed no abnormalities. Topiramate level on the third day post-ingestion was 9.4 mcg/mL, and 4.2 mcg/mL on the fourth day. Patient became oriented to family and regained normal gait on the fourth day. Her slurred speech persisted until the sixth day after ingestion. Conclusion. Topiramate is an anti-epileptic drug with multifactorial mechanisms of action not entirely understood. We report here a 33-month-old girl with prolonged neurologic symptoms including hallucination, slurred speech, and severe ataxia after acute topiramate ingestion. This is the first pediatric case report of hallucination and prolonged neurologic symptoms with acute topiramate ingestion.

Keywords :

• Topiramate toxicity
• Antiepileptic drug
• calcium channels