Contingent methadone delivery: effects on illicit-opiate use.

This study examined the effects of contingent vs. non-contingent delivery of a methadone dose supplement on relapse to illicit opiate use in the context of a methadone outpatient detoxification program. Following a 3-week methadone stabilization period on 30 mg, patients (N = 39) were randomly assigned to a contingent, a non-contingent, or a control treatment group. All patients received identical gradual reductions in their assigned methadone dose. During the dose reduction period (weeks 4-11), members of the contingent (N = 13) and non-contingent groups (N = 13) could obtain daily methadone-dose supplements up to 20 mg, but contingent group members could obtain supplements only if their most recent urinalysis results were opiate negative. Control subjects (N = 13) did not have dose increases available. The contingent group presented significantly lower opiate-positive urines during weeks 8-11 (14% positive) of the detox than the non-contingent (38% positive) or control (50% positive) groups. Additionally, the availability of extra methadone improved treatment retention and increased clinic attendance above levels observed in the control group. The potential for further use of methadone's reinforcing properties in the treatment of opiate dependence is discussed.