Tehran University of Medical Sciences Case Reports in Clinical Practice 2538-2683 10 2 2025 10 15 51 53 Shokouh Gheibi Razi Educational and Therapeutic Psychiatric Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran. Mohammad Aidin Farahvash School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Morvarid Ahadi Psychiatry Department, Psychosis Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran. 2025 04 10 2025 08 31 Pseudologia fantastica is characterized by habitual, elaborate, and often fantastical fabrications that the patient recognizes as untrue. We report a case of a 24-year-old male with bipolar disorder and adult ADHD whose treatment included mood stabilizers and atomoxetine, which improved psychiatric symptoms but had minimal effect on the pseudologia. This case highlights the persistent nature of pseudologia fantastica and its diagnostic and therapeutic complexity, calling for further investigation into its management. https://crcp.tums.ac.ir/index.php/crcp/article/view/1038 https://crcp.tums.ac.ir/index.php/crcp/article/download/1038/713