Brain injuries can predispose as well as precipitate psychiatric disorders. The course of a pre-existing psychiatric disorder may get altered due to brain injury. Alteration of the symptoms of the on-going psychiatric disorder due to brain injury may produce diagnostic dilemma. Presence of brain injury also limits the options of pharmacological treatments. Prolongation of the neuropsychiatric symptoms due to brain injury also produces significant morbidity compromising the quality of life. Treatment response and propensity to develop side effects to psychotropic medications also increase following brain injury. We describe here the case of an adolescent male, in whom brain injury altered the mood symptoms significantly. The challenges in management and the outcome are also discussed with review of literature.