Case report
Primidone-induced hyperammonemic encephalopathy in a patient with cerebral astrocytoma

https://doi.org/10.1054/jocn.2001.1011Get rights and content

Abstract

A case of a patient with astrocytoma who showed somnolence and asterixis one month after tumour resection is presented. Although primidone had been prescribed preoperatively for five years and the same dose was maintained after the operation, the serum concentration of the primidone metabolite phenobarbital was elevated and she demonstrated hyperammonemic encephalopathy, which disappeared on withdrawal of the drug. A description of this seldom reported phenomenon during primidone therapy is given, with reference to valproate cases.

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Correspondence to: Hiroyuki Katano, MD Department of Neurosurgery, Nagoya City Higashi General Hospital, 1-2-23 Wakamizu, Chikusa-ku, Nagoya 464-8547, Japan. Tel.: +81-52-721-7171; Fax: +81-52-721-1308; E-mail: [email protected]

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