Delayed Neuropsychiatric Sequelae of CO Poisoning

Carbon monoxide poisoning as a suicide method is relatively uncommon in Malaysia. Available data reported that the rate for suicide by carbon monoxide poisoning accounted for less than 1% in Malaysia in 1995 and the figure remained the same in 2011 [1]. The health risks associated with carbon monoxide vary with its concentration and duration of exposure. The toxic effects range from subtle cardiovascular and neurobehavioral effects at low concentrations to unconsciousness and death after prolonged exposures or after acute exposures to high concentrations of carbon monoxide [2]. Many physicians and psychiatrists are unfamiliar with this form of poisoning and have difficulty in recognizing the neuropsychiatric sequelae especially when the presentation is delayed. Typical presentations of delayed neuropsychiatric sequelae would be apathy, disorientation, amnesia, hypokinesia, bizarre behavior, insomnia and neurological manifestations such as gait disturbance, hypertonia and tremor [3-6]. In this case, we demonstrate a typical presentation of delayed neuropsychiatric sequelae following carbon monoxide poisoning. The patient had consented for his case to be reported here.