小発作てんかんにたいするEthosuximideの使用経験

ETHOSUXIMIDE IN THE TREATMENT OF PETIT MAL EPILEPSY

I．まえがき

　抗てんかん剤としてのぞましい条件は，副作用がなく，ひとつの発作型に特効的であることであろう。

　小発作てんかんにたいしては，従来trimethadioneが使用されてきたが，発作抑制効果および副作用に関してこの条件に欠けるところが多かつた。このため，小発作てんかんに，より有効な薬剤の開発が待たれていたが，Zimmermanら^10）によつてsuccinimide誘導体のなかにすぐれた抗てんかん作用を有するものがあることが紹介された。

21 patients affected with petit mal were treated with a new anticonvulsant of the succimide group, ethosuximide.

The results obtained were as follows.

1) 18 patients out of all cases showed improve-ment and 9 of them were completely freed from petit mal. 6 out of 14 patients having absence, were completely controlled, and 6 other patients showed some improvement. 2 patients, who had petit mal automatism, were entirely freed from attack. Of the 5 patients with myoclonic seizure, the symptom was controlled completely in one and to lesser extents in three others.

2) Out of the 9 patients, having grand mal as well as petit mal, only one was moderately benefited in the treatment of grand mal by the exclusive use of ethosuximide.

3) The improvement of EEG pattern was observ-ed in 7 cases who were treated with ethosuximide more than 5 weeks, and in 6 cases EEG remained unchanged. 3c/s spike and wave was more sensitive to ethosuximide medication than irregular spike and wave complex or multiple spikes and wave. It seem-ed that clinical symptoms improved in parallel with the EEG.

4) Side effects were observed in 8 out of the 21 cases. 3 patients complained of such digestive distur-bances as loss of appetite, vomitting and diarrhoea. 2 patients suffered from skin rash during a short pe-riod. One had singultus. 3 patients felt drawsy. Schizophreniform features appeared in one case. There were no abnormalities shown on the labora-tory tests. The same dosages were maintained in all the cases except the one which developed schizop-hreniform psychosis, in which reduction of dosage was deemed advisable. All the side effects disap-peared in a few days. There were no cases in which significant side effects called for discontinuation of the medication.

5) Comparison of their therapeutic efficacy has shown ethosuximide to be more effective than trime-thadione in petit mal epilepsy. In 6 cases better effects were observed with smaller doses of ethosu-ximide. In one case equal effect was shown by equal doses and in 6 other cases greater benefits were realized with ethosuximide in larger doses than tri-methadione.

6) The dose must be individualized according to the patient's age and symptoms. In our cases the daily administration of 0.6gm. to 1.0 gm. was nec-essary to effect seizure control. Children under 10 years of age receiving more than 0.6 gm. a day and those above 10 years in whom the dose was above 0.75gm., had some side effects.