Introduction: Carbon monoxide (CO) poisoning is a prevalent lethal condition. The clinical feature of this type of poisoning varies from headache and nausea to more severe conditions. After recovery from the acute intoxication, neurological or behavioral problems may emerge. In 3%-40% of cases, delayed neuropsychiatric syndrome (DNS) in post CO poisoning, generally develops within few weeks after a preliminary remission from acute poisoning.
Case Presentation: We report a patient with relatively suitable premorbid. He was admitted to the hospital with fire burning, co poisoning and discharged home with good general conditions and mental status by receiving normal baric oxygen 100%. later in post-operative management of skin graft he developed a fulminant neurological deficit by impaired memory and concentration, loosening of association, disorientation to place, time and person, agitation, aggression, mood labiality, urinary incontinency and encopresis, slow psychomotor retardation, false and approximate answers to questions, auditory and visual hallucination, staring and inappropriate laughing. As the patient was not responsive to neurological treatment, he was referred to psychiatric service. DNS in this patient resolved gradually during a short period of psychopharmacotherapy and supportive psychotherapy.
Conclusion: CO poisoning may lead to neuropsychiatric sequel and neuroimaging changes which could be reversible.