The effect of sertraline on methadone plasma levels in methadone-maintenance patients

The authors examine methadone plasma levels in 31 depressed methadone-maint ained opiate addicts enrolled in la 12-week placebo-controlled, double-blin d study of sertraline. Between baseline and week 6, patients out sertraline showed a mean increase in methadone plasma level/dose (P/D) ratio of 26% ( SD = 43% range -32% to +118%), while patients on placebo showed a mean decr ease of 16% (SD = 27%) range -62% to +50%. This difference was significant (p < 0.02). The sertraline and placebo groups did not differ in reported si de effects or methadone dose adjustments. Between weeks 6 and 12, methadone P/D in the sertraline group decreased back towards baseline and the treatm ent groups did not differ significantly at week 12. The results suggest ser traline may produce a modest increase in methadone serum levels over the fi rst six weeks of treatment. Depression and anxiety disorders are common in methadone-maintained patients. Serotonin uptake inhibitors are attractive c hoices for treatment due to their low toxicity and low abuse potential; but these agents variously inhibit isoenzymes responsible for the metabolism o f methadone. Clinicians treating: depressed or anxious methadone patients w ith second-generation antidepressants should monitor for clinical signs of increased or decreased methadone levels and consider monitoring serum metha done levels.