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

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. 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. ‎ 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). 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. ‎