Clinical Improvement Following Multimodal Treatment in Depersonalization-Derealization Disorder: A Case Report.

Depersonalization-derealization disorder (DPD) is characterized by persistent or recurrent detachment from the self or the surrounding environment with preserved reality testing. Because established treatment evidence remains limited, individualized therapeutic strategies are often required. This report describes a patient with derealization, emotional blunting, poor memory, slowed reactions, and impaired attention. Psychiatric evaluation showed marked depersonalization-derealization symptoms, with a Cambridge Depersonalization Scale (CDS) score of 147, a 24-item Hamilton Depression (HAMD-24) Rating Scale score of 8, a 14-item Hamilton Anxiety (HAMA-14) Rating Scale score of 5, and a MATRICS Consensus Cognitive Battery (MCCB) composite T-score of 49. The patient underwent a stepwise multimodal treatment approach that included transcranial direct current stimulation, pharmacotherapy with duloxetine and tandospirone, duloxetine dose optimization, lamotrigine augmentation and titration, and later gradual medication tapering under follow-up monitoring. Clinical improvement was observed during longitudinal assessment. This case highlights the practical value of a monitored, sequential, and multimodal treatment strategy for a patient with DPD. Although the findings are limited to a single case, the observed temporal association between intervention and improvement provides a hypothesis-generating clinical observation and supports the need for systematic studies of multimodal treatment approaches in DPD.