Patterns of non-compliant buprenorphine, levomethadone, and methadone use among opioid dependent persons in treatment

Background: The non-compliant use of opioid substitution treatment (OST) medicines is widespread and well-documented. However, less is known about characteristics of non-compliant OST medicine use and the factors that predict it. The two main goals of this study are to compare characteristics of non-compliant levomethadone, methadone, and buprenorphine use and to explore factors that may differentially predict it among opioid dependent persons in treatment. Methods: Data from 595 opioid dependent patients with non-compliant OST medicine use were analyzed. Characteristics of use between substances were compared using chi-squared tests and predictive factors were explored through multinomial logistic regressions. Results: Non-compliant levomethadone and methadone use was characterized by more frequent parallel consumption of other psychoactive substances and intravenous use, whereas buprenorphine was more often procured without a prescription. Regarding predictive factors, methadone was perceived to relieve withdrawal symptoms better than buprenorphine and levomethadone was perceived as being better at modulating the effects of other substances and worst at enhancing mood. Conclusions: Patterns of non-compliant use differ according to OST medicine. These patterns are considered with the reduction of non-compliant use and the improvement of treatment in mind.