This article aims to review the concept of epilepsy-specific psychiatric disturbance, Interictal Dysphoric Disorder (IDD), focusing on issues related to its core symptoms and methodological pitfalls. In the psychiatric literature, an epilepsy-specific pleomorphic mood disorder has been long recognized and described as IDD, a condition characterized by eight symptoms, which are grouped into four labile depressive symptoms, two labile affective symptoms, and two specific symptoms. The existence of IDD is still a matter of debate because of several methodological issues. The main features of IDD, such as dysphoria and irritability, lack precise and clear definition. This review article explores the different definitions and approaches towards both terms described in the psychiatric literature and the rationale for modifying the diagnostic process of IDD.
Keywords: DSM-5 (Diagnostic and Statistical Manual of Mental Disorders); dysphoria; interictal dysphoric disorder (IDD); irritability; patients with epilepsy (PWE).