Plasma levels of anticonvulsant drugs were monitored (during continuous therapy, withdrawal and readministration of therapy) in 13 cases of partial epilepsy with elementary or complex symptomatology while stereo-EEG study was being carried out. The stereo-EEG focus temporal in 10 patients (unilateral in 9 and bilateral in 1), parietal in 2, mutlifocal (frontotemporal) in 1. Two of the authors' cases were treated with monotherapy of carbamazepine; 7 patients received combined therapy of phenobarbital and diphenylhydantoin, 2 had a combination of phenobarbital and carbamazepine and the last 2 phenobarbital and clonazepam. The mean duration of withdrawal of therapy was 6 days, ranging from 4 to 9 days. The medical treatment was always stopped abruptly and the decrease of anticonvulsant plasma levels was followed with daily controls. During initial decrease of anticonvulsant plasma levels, electrical seizures without clinical signs are usually present at stereo-EEG; electroclinical seizures appear when 'minimal' therapeutic levels are approached. When anticonvulsant plasma levels are under 'minimal' therapeutic levels, spreading of ictal activity to cortical areas, previously unaffected takes place and secondary generalization may occur. During this period severe intensification of ictal and interictal activities makes very difficult the identification of the primary epileptogenic focus. The correlation of interictal and ictal electrical activities in each explored cortical and subcortical area with anticonvulsant plasma levels will be discussed in detail.
|Journal||Electroencephalography and Clinical Neurophysiology|
|Publication status||Published - 1977|
ASJC Scopus subject areas
- Clinical Neurology