Glucose transporter type 1 deficiency syndrome (GLUT1DS) is a rare neurological disorder characterized by a wide spectrum of symptoms: epilepsy, movement disorders and neurocognitive impairment. The gold standard treatment for GLUT1DS are ketogenic dietary therapies (KDTs), specifically classical ketogenic diet (CKD). Despite the benefits, CKD often represents a challenge for patients and their families since meal preparation is extremely demanding and deviates a lot from normal diet. To assure an optimal compliance to CKD a psychological support for parents and patients with GLUT1DS is highly recommended. Specifically, a psychoeducational intervention that ameliorates the knowledge about the illness and its therapy improves treatment' s adherence and efficacy. The aim of this case report is to investigate the effectiveness of a psychoeducational program, partially implemented through telepsychology, based on the theoretical model of Cognitive Behavioral Play Therapy (CBPT) to support KDT knowledge and adherence in a patient with GLUT1DS who presented a worsening of her clinical picture due to a sparse knowledge of KDTs principles which determined a low adherence. Thus, with this case report we propose a model of intervention with psychoeducation in a patient with a complex chronic disease.