難治性てんかんのClonazepamによる治療経験—精神運動発作を中心に

Clinical Evaluation of Clonazepam (Ro 5-4023) on Epileptic Seizures: Especially on Psychomotor Seizures

I．はじめに

　現在までに数多くのすぐれた抗てんかん剤が開発されてきたにもかかわらず，長期間の専門的治療にも抵抗する難治性てんかんが今なお多く残されている。さらに優れた効果をもち，副作用の少ない新しい抗てんかん剤の開発は医療における現代的課題の一つといえよう。

　こうした新しい抗てんかん剤の模索の中で，この十年来，benzodiazepine系の薬剤が注目されてきている。すなわち，diazepam，nitrazepamをはじめとするbenzodiazepine系の薬剤はWest症状群，Lennox症状群を中心に優れた抗てんかん作用を有することが数多く報告されている^{17,20,26）他}。

　Clonazepam was administered via p.o. and i.v. routes to patients with incurable epilepsy mainly consisting of psychomotor seizure. The following results were obtained:

　1. Clonazepam of 1.5-14mg/day was administered via p.o. route to 32 patients with other anti-epileptic drugs. The effective rate was 75%. The average effective dose was 3.5mg/day. The drug was remarkably effective in patients with psychomotor seizure. Of 14 patients with psychomotor seizure, 8 patients (57%) responded excellently and 4 (29%) responded effectively. The drug was considered to be worth employing in this kind of incurable epilepsy. Furthermore, as seen in other reports, this drug showed effectiveness in the other spasm types, particularly Lennox syndrome and West syndrome.

　2. In general, administration of more than 3 months fairly lowered the effective rate, but in the most of cases sufficient antiepileptic effects which en-couraged continuous administration were seen when administered continuously more than 6 months.

　3. Two patients with status epilepticus were administered 1-2mg of clonazepam via i.v. route. In both of them complete inhibition of spasm, clearance of consciousness, and normalization of EEG were seen just after the injection. These effects continued for about 20-25 minutes. In our experience these effects were more remarkable than those when administered diphenylhydantoin and diazepam.

　4. When administered orally, many patients complained of drowsiness as a side effect, but this could be reduced by changing the dosage of this drug or combination of the other anti-epileptic drugs. Of 35 cases drop out cases because of this side effect were 3 cases. Other side effects were not seen except one case of hypersalivation, and results of clinical examinations could not find any adverse reactions attributable to this drug.