The new diagnosis of disruptive mood dysregulation disorder (DMDD) was introduced in the Diagnostic and Statistical Manual of Mental Disorders, fifth edition, to address the overdiagnosis of bipolar disorder in children and adolescents. However, there are ongoing debates about its nosology given chronic persistent irritability in children and adolescents has contextual valence. Those meeting the criteria for DMDD may, in fact, have an oppositional defiant disorder, attention deficit hyperactivity disorder, or other behavioral disorders. Similarly, in the last few years, there are many different types of treatment studies that have also yielded mixed results. These counterintuitive findings need a meticulous review for a wider debate given its clinical utility for patients, families, and practicing clinicians.