We cannot find the definite etiology in most epileptic patients although the accurate neurological examination. In such epileptic patients, longterm medications of inadequate drug or dosage induce freguently many iatrogenic disorders. Nearly all side effects are acute or subacute forms which have been found obvious etiology and have almost reversible symptoms, but almost chronic iatrogenic disorders have unknown etiology and cause trouble problem due to irreversible changes.
The auther describes the case histories of three patients who suffered from anticonvalsant intoxication, especially dilantin.
The acute skin rashes which the first patient had presented, disappeared completely after the ceasation of dilantin medication.
The second patient showed the clinical picture of the acute cerebellar syndrome. The patient improved when the drug was withdrawn but abnormal signs persisted for several months. Phenobarbital and diagepam were substituted for dilantin and in one year all iatrogemic disturbances were completely disappeared.
The third patient, however, presented the Pict= ures, which suggested the permanent cerebellar damage. After reducing the dosage of dilantin medication, the most iatrogenic disturbances, such as skin rashes, gum hypertrophy, edematous swelling of the face and gastro-intestinal symptoms, were alwost abolished, but the signs of the cerebellar dysfunction were rather worsened progressively. The patient showed the frequent seizure attacks during the high dosage of dilantin which might be due to the paradoxical exacerbation of the convulsive seizure by the high dosage of this drug.
The author suggests the third patient might have irreversible pathological changes in his cerebellum due to longterm medication, since he had chronic progressive cerebellar symptoms that had been worsened in-spite-of decreasing the dosage during last six years. It also mentioned that the inhibition of the Na+, K+, Mg++, ATPase enzyme system by dilantin may be important in causing neuronal damage, especially cerebellum.
The fact that seizure frequently seems to be increased by dilantin overdosage could also be explained on the basis of inhibition of the enzyme system causing a rise in intraneuronal sodium concentration and consequent decrease in membrane stability.
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