Methadone Overdose and Its Complications in Patients Admitted to the Toxicology Emergency Ward of Baharloo Hospital of Tehran in 2011-2012

Abstract

Background: To date, studies on methadone overdose in adults have not been reported in Iran. Hence, this study was performed to determine the frequency of methadone overdose and its associated complications in Baharloo Hospital of Tehran between August 2011 and August 2012. Methods: This cross-sectional study was done on 390 cases. All patients with methadone overdoses and positive urine screen test for methadone were included in this case study through census method. Demographic data and overdose complications, such as loss of consciousness, respiratory complications, arrhythmia, hemodynamic disturbances, and QTC interval, were recorded in the questionnaire. Data were analyzed by SPSS software and Kolmogorov Smirnov, t-test, and Chi-square tests were used for data analysis. Results: Overall, 84.1% of the samples were male and the mean age of the samples was 35.53±11.25 years (range: 15-84 years). Mean of the methadone dose used in current admissions was 96.13±52.34 mg. Concomitant drug abuse and concomitant uses of medications were seen in 25.9% and 36.9% of the patients, respectively. Respiratory depression, pulmonary edema, pneumonia, aspiration, and arrhythmia were seen in 87.9%, 26.2%, 3.3%, 7.4%, and 15.4% of the patients, respectively. There were significant differences between concomitant medications, duration of methadone use, and QTc interval prolongation and arrhythmia (P<0.05). Conclusion: Based on the findings of the present study, initial screening of ECG changes and QT interval prolongation as well as arrhythmias should be considered in patients on methadone therapy and concurrent drug abuse and co-administration of medications that lead to QT prolongation should be avoided in them.

Keywords

• Arrhythmia
• Complications
• Methadone
• Overdose
• Qtc Interval