BackgroundIt is well known that illicit use of methadone and buprenorphine is common among people with an opioid dependence. Less notice has been taken of the fact that these substances are also used for extended periods of self-treatment, as a way of handling barriers to OST. In this study, motives for self-treatment are investigated, as well as attitudes and perceived barriers to OST among drug users with an opioid dependence in Sweden.MethodThe study is based on qualitative research interviews with 27 opioid users who have treated themselves with methadone or buprenorphine for a period of at least three months.ResultsThe duration of self-treatment among the interviewees varied from 5 months to 7 years. Self-treatment often began as a result of a wish to change their life situation or to cut back on heroin, in conjunction with perceived barriers to OST. These barriers consisted of (1) difficulties in gaining access to OST due to strict inclusion criteria, limited access to treatment or a bureaucratic and arduous assessment process, (2) difficulties remaining in treatment, and (3) ambivalence toward or reluctance to seek OST, primarily due to a fear of stigmatization or disciplinary action. Self-treatment was described as an attractive alternative to OST, as a stepping stone to OST, and as a way of handling waiting lists, or as a saving resource in case of involuntary discharge.ConclusionIllicit use of methadone and buprenorphine involve risks but may also have important roles to play for users who are unwilling or not given the opportunity to enter OST. A restrictive and strict rehabilitation-oriented treatment model may force many to manage their own treatment. More generous inclusion criteria, a less complex admission process, fewer involuntary discharges, and less paternalistic treatment may lead to increasing numbers seeking OST. Control measures are necessary to prevent diversion and harmful drug use but must be designed in such a way that they impose as few restrictions as possible on the daily life of patients.