Contingent reinforcement sustains post-detoxification abstinence from multiple drugs: A preliminary study with methadone patients

This study examined the efficacy of a urinalysis-based contingency manageme nt program for preventing relapse to abused drugs following a brief residen tial detoxification. Fourteen methadone maintenance patients who were chron ic benzodiazepine users were enrolled in a 7-day inpatient benzodiazepine d etoxification and randomly assigned to receive Contingency Management (N = 7) or Standard Care (N = 7) therapy upon return to outpatient methadone tre atment. In the Contingency Management condition, a methadone take-home dose or a US $25 voucher (patient's choice) could be earned for each urine samp le submitted on a Monday, Wednesday or Friday that was free of opiates, coc aine and benzodiazepines. Data analysis and interpretation focused on withi n-group post-hoc differences due to group differences on employment and leg al status, potentially confounding baseline variables. Repeated measures an alysis of variance showed that Contingency Management patients submitted si gnificantly more drug-free urine samples during the intervention compared t o pre-detoxification (p < 0.01), whereas no significance changes were obser ved from pre- to post-detoxification in the Standard Care patients. Employm ent and legal status of patients may have facilitated response to contingen cy management procedures, but did not prevent relapse when contingency mana gement procedures were withdrawn. Overall, these preliminary results sugges t that abstinence-based contingency management is a promising strategy for preventing relapse to multiple drugs of abuse in a subset of methadone main tenance patients when abstinence has been initiated through brief inpatient treatment. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.