Abstracts

Rationale: Levetiracetam (LEV) has been classified as one of the newer anti-epileptic drugs (AEDs), and is very useful because of its rapid action and fewer adverse effects compared to the old and established AEDs. LEV was approved by the Pharmaceuticals and Medical Devices Agency and came onto the Japanese market in 2010. However, the indication at the launch was only add-on treatment for focal epilepsy including secondary generalization. Monotherapy by LEV was finally approved in Japan this year. That is not officially approved yet in the United States though. Our hospital is an acute and tertiary care teaching hospital covering neurological emergency through epilepsy. Early experience using LEV monotherapy (LEV-MT) was investigated retrospectively to demonstrate its effectiveness, safety, and potential for the near future in epilepsy treatment.Methods: Three hundred and fifty patients aged 15 years and older were treated by LEV to suppress seizures from January through December of 2014. The age ranged from 15 to 99, and the mean age was 43.6 years old. Female patients were 173 and male were 177. Medical records of all patients were examined retrospectively, and changes in seizure frequency before and after the treatment by LEV were especially investigated.Results: Ninety-two patients (26%) were treated by LEV-MT. In 41 patients, LEV was prescribed as the first AED to control seizures (initial monotherapy; IMT). In 51 patients, LEV was prescribed as add-on therapy and then the antecedent AEDs were tapered off (switch to monotherapy; STM). Diseases that required LEV were wide-ranging. Some of the patients were treated for brain tumor (n=14), hemorrhagic stroke (n=11), and ischemic stroke (n=6) on an emergency or acute basis. The other patients were treated for mesial temporal lobe epilepsy (n=22), and different types of epilepsy (n=19). The rate of seizure freedom was 84% in IMT. In non-seizure free patients by antecedent AEDs, 44% patients got seizure freedom in STM. Including seizure free patients by antecedent AEDs, total rate of seizure freedom was 55% in STM. Reasons why LEV was chosen for treatment were as follows. Some patients were taking important drugs such as warfarin, and then LEV was a choice because of much fewer drug-drug interactions (n=21). The antecedent AEDs were not effective to suppress seizures (n=19). The antecedent AEDs caused significant adverse events (n=15). Seizure frequency was significant more than daily seizures and immediate action was necessary (n=15). Female patients were expecting a baby (n=7). Eighty patients out of 92 continued LEV-MT. Some adverse effects were reported and were somnolence in 12 patients, and irritability in 2. However, only 2 of them discontinued LEV-MT.Conclusions: LEV-MT was well investigated and demonstrated its effectiveness in seizure control and convenience in many clinical circumstances. LEV could be used from acute patient care through clinic basis. Therefore LEV-MT will expand its uses and will be one of the important choices instead of the established AEDs.