Journal of Research in Pharmacy Practice

Methadone toxicity in a poisoning referral center

Authors

. Fatemeh Taheri 1
. Ahmad Yaraghi 1
. Ali Mohammad Sabzghabaee 1
. Maryam Moudi 2
. Nastaran Eizadi‑Mood 3
. Farzad Gheshlaghi 3
. Ziba Farajzadegan 4

1 isfahan Clinical Toxicology Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

2 Department of Biology, University of Putra Malaysia, Malaysia

3 Isfahan Clinical Toxicology Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

4 Department of Health and Social Medicine, Isfahan University of Medical Sciences, Isfahan, Iran

Abstract
Objective: Methadone poisoning can occur accidentally or intentionally for suicide or 
homicide purposes. The aim of this study was to evaluate the epidemiological and clinical 
manifestations of Methadone poisoning.
Methods: A descriptive analytical study was performed from 2010 to 2012 in the poisoning 
emergency and clinical toxicology departments of Noor hospital affiliated with Isfahan 
University of Medical Sciences (Isfahan, Iran). All patients with Methadone poisoning within 
this period of time were investigated. Different variables were recorded in a checklist.
Findings: A total of 385 patients were studied. About 85.7% had ingested only Methadone 
and 14.3% had ingested other medications with Methadone. Mean ± standard deviation 
of the age was 32.1 ± 15 years (range: 1‑90). Most of the patients were male (76.4%). 
Nearly 40% of the patients were narcotic addicts, 25.5% were addicts under surveillance of 
Methadone maintenance therapy centers and 34.5% were non‑addicts. Intentional poisoning 
was observed in most of the patients (57.7%). Most of the patients had a low level of 
consciousness on admission (58.2%). Respiratory depression and hypotension was observed 
in 35.6% and 12.7% of the cases as the most common symptoms. Regarding vital signs, there 
was a significant difference in respiratory rate on admission among different evaluated 
groups (P = 0.02). Length of hospital stay was 18.79 ± 0.72 h (range: 4‑240 h, median: 15 h). 
About 57 patients (25.8%) from the intentionally poisoned patients and 19 patients (12.3%) 
from the unintentionally poisoned patients had a history of psychiatric disorder (P = 0.001). 
Most of the patients survived without complications.
Conclusion: Addiction, age, gender, attempt to suicide and a history of psychiatric disorder 
were of the most important factors effective in Methadone poisoning, which should be 
considered in the public training and prevention of poisoning.

Keywords

Methadone
overdose
poisoning
toxicity
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Journal of Research in Pharmacy Practice
Volume 2, Issue 3
Summer 2013
Pages 130-134

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