Moore Kelly, Dixit Deepali, Wagner Mary
Hospital of Special Surgery, New York, NY, USA.
Rutgers, The State University of New Jersey, Piscataway, NJ, USA.
J Pharm Technol. 2016 Feb;32(1):34-36. doi: 10.1177/8755122515605849. Epub 2015 Sep 11.
To report a case of hyperammonemia associated with the interaction between topiramate and valproic acid. We present a patient case with topiramate-related hyperammonemia. The patient was on topiramate prior to admission and presented with an elevated ammonia level following 2 doses of valproic acid. The increased dosing frequency of valproic acid further exacerbated the hyperammonemia. On discontinuation of topiramate and the tapering of the dose of valproic acid the patient's ammonia level returned to normal. Valproic acid-induced hyperammonemic encephalopathy is well documented and there are several proposed mechanisms. The interaction between valproic acid and topiramate causing drug-induced hyperammonemia encephalopathy is documented in several case reports. The interaction is associated with the addition of topiramate to a patient's medication regimen that previously included valproic acid. Topiramate also has several proposed mechanisms for predisposing patients for hyperammonemia. There are limited data on topiramate monotherapy or long-term use of topiramate use causing hyperammonemia-associated encephalopathy or enhancing hyperammonemia with the addition of valproic acid. This case supports topiramate-related hyperammonemia and the pharmacodynamic interaction with the co-administration of valproic acid.
报告一例与托吡酯和丙戊酸相互作用相关的高氨血症病例。我们呈现了一例与托吡酯相关的高氨血症患者病例。该患者入院前服用托吡酯，在服用2剂丙戊酸后出现氨水平升高。丙戊酸给药频率增加进一步加重了高氨血症。停用托吡酯并逐渐减少丙戊酸剂量后，患者的氨水平恢复正常。丙戊酸诱导的高氨血症性脑病已有充分记录，且有多种提出的机制。丙戊酸与托吡酯之间相互作用导致药物性高氨血症性脑病在多篇病例报告中均有记载。这种相互作用与在先前已包含丙戊酸的患者药物治疗方案中添加托吡酯有关。托吡酯也有多种致使患者易患高氨血症的机制。关于托吡酯单药治疗或长期使用托吡酯导致高氨血症相关脑病或在加用丙戊酸时增强高氨血症的数据有限。该病例支持与托吡酯相关的高氨血症以及与丙戊酸联合使用时的药效学相互作用。
