Therapeutic Drug Monitoring of Topiramate in Status Epilepticus / 대한간질학회지

ABSTRACT

PURPOSE: Status epilepticus (SE) is a pathologic state where pharmacokinetic alterations can be more pronounced and more rapid than during the other epileptic states. The consequences of such changes can exert negative influences on the timely adequate treatments for stopping uncontrolled seizures during SE. Topiramte (TPM) is one of new antiepileptic drugs with high efficacy in epilepsy, which can also be effectively used in SE. The aim of this study was to evaluate the pharmacokinetic changes during the SE by an analysis of the therapeutic drug monitoring (TDM) of TPM in patients with SE. METHODS: We retrospectively analyzed 49 serum measurements of TPM from 22 subjects with SE. The serum concentrations of TPM were measured by HPLC-tandem mass spectrometry. TDM data were categorized into malignant status epilepticus (MSE), refractory status epilepticus (RSE), and non-status epilepticus (NSE) groups. We compared concentration-to-dose ratio (CDR) among those groups. RESULTS: Among 49 cases, 11 were in MSE, 19 in RSE, and 19 in NSE. The daily dose of TPM was higher in MSE (median, interquartile range 600, 600-800 mg) than in RSE (300, 250-600 mg) and NSE (200, 150-400 mg). The daily dose adjusted for body weight was also higher in MSE (12.2, 10.4-13.9 mg/kg) than in RSE (4.5, 3.8-12.2 mg/kg) and NSE (4.1, 2.3-7.1 mg/kg) (p0.1). However, the concentration-to-dose ratio (CDR) was significantly lower in MSE (0.41, 0.35-0.59 kg/L) and RSE (0.85, 0.39-1.23 kg/L) than in NSE (1.72, 0.96-2.24 kg/L) (post hoc analysis, p<0.005, 0.05). CONCLUSIONS: The serum concentrations of TPM can be influenced by SE, particularly in MSE. The higher range of dose of TPM could be needed for an adequate treatment of SE.