Aims: During 3 months where contingency management (CM) had an escalating value for each consecutive drug-free urine (escalating CM), cocaine- and heroin-abusing patients significantly increased drug-free urines. The 'escalating CM' was eliminated during months 4-6 to assess any reduction in drug-free urines.
Design: Patients who completed a 3-month, randomized, double-blind, trial evaluating CM versus non-CM and desipramine (DMI) versus placebo, had an 'escalating CM' eliminated during months 4-6. The CM and non-CM groups were compared using thrice-weekly urine samples.
Setting: Out-patient buprenorphine maintenance for 6 months.
Participants: All 75 of the 160 original study patients who completed month 3 of the clinical trial.
Intervention: The 'escalating CM' was eliminated for all 3 months and during months 5 and 6 the response requirement was also increased to two and then three consecutive drug-free urines in order to obtain a voucher.
Measurements: Urine toxicology for opiates and cocaine.
Findings: After eliminating the 'escalating CM', the CM group showed a decline in combined opioid- and cocaine-free urines. This decline within the CM group was greater in those treated with DMI than placebo.
Conclusions: Buprenorphine with DMI maintained drug abstinence after eliminating the 'escalating CM', but not after increasing the response requirement, suggesting the need for more intensive psychosocial interventions during CM.