Paroxysmal Oral Dyskinesia in Glucose Transporter Type 1 Deficiency Syndrome: Two Cases Demonstrating Patient-Specific Precipitating Factors

Introduction

Nonepileptic paroxysmal movement disorders are key clinical features of glucose transporter type 1 deficiency syndrome (Glut1DS); however, paroxysmal oral dyskinesia confined to the orofacial region has rarely been described. Here, we report two patients with classical Glut1DS who experienced transient nonepileptic paroxysmal oral dyskinesia. Case Presentations: In both patients, consciousness was preserved, episodes lasted approximately 30 min, and spontaneous resolution occurred with rest. In Patient 1, oral dyskinesia accompanied by drooling and dysphagia was provoked by sustained oral movements during eating, and appropriately timed preprandial ketogenic supplementation (30 min before dinner) reduced attack frequency. The episodes appeared after initiation of aripiprazole treatment and improved following its discontinuation. In Patient 2, episodes were triggered by metabolic stressors, such as fatigue, physical illness, and sleep deprivation, without a clear association with eating-related oral movements.