The effects of racemic D,L-methadone and L-methadone in substituted patients - a randomized controlled study. Verthein U, Ullmann R et al. Drug and Alcohol Dependence 2005 80;2:267-271
Dear Colleagues,
This interesting and definitive study from Hamburg informs us that pure 'levomethadone' and racemic (mixed levo-dextro 50:50) methadone are clinically equivalent in the expected ratio of 1:2 with no significant difference in withdrawal symptoms or other clinical aspects of maintenance treatment. The pure enantiomer is more expensive and thus should probably be phased out in Germany, the only country where it had widespread use.
Despite no real evidence, some have speculated that certain methadone side effects might be due by the inactive L or 'dextro' component. This careful, cross-over, randomised trial with 75 subjects has only found mild, transient differences in sudden experimental substitutions of medication. These did not reach significance and confirm what was done by Judson in 1976.
