Display Settings:


Send to:

Choose Destination
See comment in PubMed Commons below
Fundam Clin Pharmacol. 2011 Aug;25(4):503-10. doi: 10.1111/j.1472-8206.2010.00871.x. Epub 2010 Sep 6.

QT interval prolongation: prevalence, risk factors and pharmacovigilance data among methadone-treated patients in France.

Author information

  • 1Unité de Pharmacoépidémiologie EA3696, Inserm, U558, Faculté de Médecine Purpan, Université de Toulouse, UPS, 37 Allées Jules Guesde; F-31000 Toulouse, France.


Several reports have suggested the role of methadone in QT prolongation, Torsades de Pointes (TdP), and ventricular arrhythmia. The aim of this study was to identify the frequency of QT interval prolongation and QT dispersion among a population of addict patients treated with methadone, completed by the description of cardiac events reported to the French pharmacovigilance system. QT interval (corrected with the Bazett's method) and dispersion were measured on a cohort of patients treated with methadone during their visit to addiction specialized centers in Southwest of France. Whenever possible, methadone blood concentrations were measured. In addition, reports concerning methadone were searched in the French Pharmacovigilance database from 1996 to 2007. The cohort included 42 patients with mean QTc length of 414.3 ± 28.5 ms and mean QT dispersion of 66.0 ± 41.1 ms. None of the patient presented a QTc above 500 ms. These values were higher in patients with recent increase in methadone dose, use of tobacco or drugs prolonging QT, and history of cardiac disease. We found five cases of QT prolongation (3 TdP) and seven cases of sudden deaths in the French pharmacovigilance database (2.2% of methadone reports). Most of these events occurred after introducing methadone or another drug potentially interacting with methadone. Methadone can prolong the QT interval at dose usually used for addiction maintenance treatment in France. A cardiac evaluation, with at least a systematic ECG, could be useful during methadone treatment, particularly in case of recent modification of the regimen.

© 2010 The Authors Fundamental and Clinical Pharmacology © 2010 Société Française de Pharmacologie et de Thérapeutique.

[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Blackwell Publishing
    Loading ...
    Write to the Help Desk