Demographic characteristics and psychosocial backgrounds of patients with dextromethorphan overdose in Japan: A multicenter prospective observational study.

AIM: Few studies in Japan have described young patients presenting to emergency departments after dextromethorphan overdose in detail. Therefore, we aimed to investigate the demographic characteristics and psychosocial backgrounds of patients who presented to emergency departments in Japan after dextromethorphan overdose. METHODS: This was a multicenter, prospective, observational study with nonconsecutive enrollment. A standardized questionnaire regarding dextromethorphan overdose and the Drug Abuse Screening Test-20 (DAST-20) were administered in eight emergency departments in Japan. Continuous variables are presented as medians and interquartile ranges. RESULTS: In total, 78 patients were included. The median age was 20 years (17.0-22.0), and 64 patients (82.1%) were female. Fifty-six (71.8%) patients engaged in social activities. Fifty-one patients (65.4%) stated that the purpose of the overdose was suicide/self-harm. The number of patients who reported that the source of information on dextromethorphan overdose was social networking services and internet searches was 27 (35.1%) and 29 (37.7%), respectively. Fifty-eight patients (74.4%) reported that dextromethorphan was purchased from a retail store. Among 66 respondents, 40 (60.6%) had moderate or higher DAST-20 scores. On comparing the younger group aged 10-19 years (n = 38) and the older group aged ≥20 years (n = 40), the number of patients who indicated that the source of information on dextromethorphan overdose was internet searches in the former group (19, 50.0%) was significantly higher than that in the latter group (10, 25.0%). CONCLUSION: Dextromethorphan overdose predominantly involved young women, and drug-related problems were common.