Suchergebnisse

The clinical effectiveness of <i>l</i>-methadone maintenance treatment (LMMT) carried out using <i>d,l</i>-methadone or <i>l</i>-methadone have been compared with ambulatory heroin-dependent subjects. A total of 40 heroin-dependent subjects, previously maintained on <i>l</i>-methadone in Frankfurt am Main, were divided into two groups under randomised double-blind conditions and received either an equivalent dose of <i>l</i>-methadone as <i>d,l</i>-methadone or remained on the previous <i>l</i>-methadone treatment. Requests for a change in the dose of <i>d,l</i>-methadone and <i>l</i>-methadone were recorded, urine samples for determination of illicit drug use were collected and the individual level of opiate craving was determined over a 22-day observation period. There was no significant difference between the two groups in the number requests for a dose change (dose increase <10%). However, there was a significant increase in heroin use in the group which continued to receive <i>l</i>-methadone. Although there was less variability in opiate craving in the group receiving <i>d,l</i>-methadone, the mean intensity of opiate craving did not differ between the two groups. The mean <i>l</i>-methadone dose:<i>l</i>-methadone plasma concentration ratio, an index of the bioavailability of <i>l</i>-methadone in individual subjects, showed no significant change when the treatment was changed to <i>d,l</i>-methadone. The mean <i>d</i>-methadone:<i>l</i>-methadone plasma concentration ratio was 1.17. There was no significant difference between these ratios for day 15 and day 22. The mean <i>l</i>-methadone:EDDP plasma concentration ratio in the <i>l</i>-methadone group was 22.2 and the <i>d,l</i>-methadone:EDDP plasma concentration ratio was 18.4 . The plasma EDDP concentration in the <i>d,l</i>-methadone group increased 3-fold after starting treatment with <i>d,l</i>-methadone. These findings suggest that <i>d,l</i>-methadone can be used in methadone maintenance treatment of heroin-dependent subjects but that further studies are required to evaluate pharmacokinetic interactions between methadone enantiomers.