FLUOXETINE IS INEFFECTIVE FOR TREATMENT OF COCAINE DEPENDENCE OR CONCURRENT OPIATE AND COCAINE DEPENDENCE - 2 PLACEBO-CONTROLLED, DOUBLE-BLIND TRIALS

Cocaine dependence has proved difficult to treat, whether occurring al one or in combination with opiate dependence. No medication has been d emonstrated to be uniquely effective. Fluoxetine was examined as a can didate in two randomized, double-blind, placebo-controlled trials, one with cocaine-dependent patients (study 1) and the other with patients both cocaine and opiate dependent (study 2). It was selected for know n specific action, antidepressant effects, minimum side effects, and d ata showing reduced cocaine effect and self-administration. Clinic vis it frequency requirement, a variable with implications for treatment a nd cost, was also examined in study 1. A total of 228 patients in stud y 1 and 21 patients in study 2 completed consent and intake procedures . Patients with serious medical or DSM-III-R diagnoses other than coca ine dependence (study 1) or opiate and cocaine dependence (study 2)wer e excluded. Study 1 patients were assigned to one of two visit frequen cy schedules (2 or 5 days/week) and one of three medication doses (0, 20, or 40 mg of fluoxetine/day). Study 2 patients received placebo or 20 mg of fluoxetine and 65 to 80 mg of methadone and attended the clin ic 5 days/week. An patients participated in individual therapy session s. Urine screens were conducted twice weekly. A fluoxetine dose respon se relationship emerged in study 1 for retention with groups from best to worst being placebo, 20 mg, and 40 mg. Dose effect order was the s ame for both visit conditions. Cocaine use persisted in all groups. Th e two visits/week condition was correlated with better retention than the five visits/week condition. A significant interaction emerged betw een intake urine and visit frequency; patients with benzoylecognine sc reens at intake used cocaine significantly less in the 5 days/week con dition, while exhibiting no reduction in the 2 days/week condition. Pa tients cocaine positive at intake were better retained with infrequent visits. In study 2, a transient reduction in benzoylecognine-positive drug screens emerged for the fluoxetine group. These complementary st udies demonstrate that fluoxetine is ineffective in reducing cocaine u se or craving; Study 1 also points to setting conditions modulating tr eatment outcome.