I'm due to start methadone tonight- 5mg daily for a week, then up to 10mg daily. But I'm also on endep and baclofen and I've been reading that endep and methadone can cause serious problems. Baclofen-Methadone has a moderate conflict, but endep and methadone is quite major.
This is what I've found out:
methadone and amitriptyline (Major Drug-Drug)
MONITOR CLOSELY: Methadone may cause dose-related prolongation of the QT interval. Coadministration with other agents that can prolong the QT interval may result in elevated risk of ventricular arrhythmias, including ventricular tachycardia and torsade de pointes, because of additive arrhythmogenic potential related to their effects on cardiac conduction. High dosages of methadone alone have been associated with QT interval prolongation and torsade de pointes. In a retrospective study of 17 methadone-treated patients who developed torsade de pointes, the mean daily dose was approximately 400 mg (range 65 to 1000 mg) and the mean corrected QT (QTc) interval on presentation was 615 msec. The daily methadone dose correlated positively with the QTc interval. Fourteen patients had at least one predisposing risk factor for arrhythmia (hypokalemia, hypomagnesemia, concomitant use of a medication known to prolong the QT interval or inhibit the metabolism of methadone, and structural heart disease), but these were not predictive of QTc interval. It is not known if any of the patients had congenital long-QT syndrome.
Now I don't know much about QT intervals etc, but I do
know that I don't want to have heart problems and end up in hospital!
Has anyone here been on both at once? Did you have problems with it? Is this info more for those on higher dosages?
I'm waiting on hearing back from my pain clinic (could take a while!
) so I thought I'd just ask on here, to see if anyone's come across this.