BackgroundPrevalence of substance use disorders, especially opioid use disorders, is high in patients admitted into forensic psychiatric settings. Opioid agonist treatment is a safe, well-established, and effective treatment option for patients that suffer from opioid dependence. Surprisingly, data on the availability and practice of opioid agonist treatment (OAT) options in German Forensic Clinics for Dependency Diseases is rare. Furthermore, essential data on the prevalence of critical incidents such as violent behavior, relapse, or escape from the clinic are missing for this particular treatment setting.Materials and methodsWe conducted an observational study on all forensic addiction treatment units in Germany (Sect. 64 of the German Criminal Code). A questionnaire on the availability and practice of OAT was sent to all Forensic Clinics for Dependency Diseases in Germany. Following items were assessed: availability and the total number of patients that received an OAT in 2018, available medication options, specific reasons for start and end of OAT, number of treatments terminated without success, number of successful treatments, and critical incidents such as violent behavior, relapse, escape and reoffending. We compared the forensic clinics that offered OAT with those that did not offer this treatment option. The data were analyzed descriptively. Mean and standard deviation was calculated for metric scaled variables. For categorical variables, absolute and relative frequencies were calculated. The two groups (OAT vs. Non-OAT institutions) were compared concerning the given variables by either using Fishers exact test (categorical variables), t-test (normally distributed metric variables), or Wilcoxon-test (metric variables not normally distributed).ResultsIn total, 15 of 46 Forensic Clinics for Dependency Diseases participated in the study (33%). In total, 2,483 patients were treated in the participating clinics, 18% were relocated into prison due to treatment termination, and 15% were discharged successfully in 2018. 275 critical incidents were reported: violence against a patient (4%), violence against staff (1.6%), escape (4.7%) and reoffending in (0.5%). In seven clinics treating 1,153 patients, an OAT was available. OAT options in forensic clinics were buprenorphine/naloxone, buprenorphine, methadone, and levomethadone. Regarding critical incidents and successful discharge, no differences were detected in the clinics with or without an OAT. In the clinics that offered an OAT, we found a significantly higher rate of treatment termination without success (p < 0.007) in comparison to clinics without an OAT program. Ninety-nine patients received an OAT, and this treatment was ended due to illegal drug abuse (57%), refusal to give a urine drug sample (71%), and cases where the OAT was given away to other patients (85%).ConclusionIn Forensic Clinics for Dependency Diseases in Germany, OAT is not available in every institution, and thus, access is limited. Critical incidents such as violent behavior against staff or patients and escape are not uncommon in these forensic treatment settings. Further studies are needed to enhance the understanding of OAT practice and the risks for patients and staff.