The impact of substitution treatment in prisons--a literature review.

Substitution treatment (ST) has established itself as a generally recognised type of treatment for opioid dependence worldwide. Although the number of countries providing ST in prison has slowly started to grow over the last years, its application in the custody setting remains controversial. ST in prison is mainly employed in form of detoxification. Maintenance treatment is provided in only a limited number of international prisons. This literature review is centred around the question: "What is known about the effectiveness of prison based ST?" Furthermore, it investigates how this knowledge can be applied to improve treatment scope and quality. Effectiveness, as defined by the examined studies, refers to short- and long-term reduction of drug use and relapse, reduction in drug use related risk behaviours, reduction in criminal conduct and recidivism, facilitating the manageability of drug using prisoners and improving their physical stabilisation. In this context, substitute dosage, treatment duration, patient retention rates, complementary psycho-social care and the effects of disrupting maintenance treatment when entering the institution are scrutinised. Results show that prison-based ST and especially prison-based methadone maintenance treatment (PMMT) can reduce drug use and injection in penal institutions. Moreover, PMMT provision can reduce injecting risk behaviours as well as drugs charges and re-admission rates. However, for PMMT to retain patients in treatment and reduce illegal drug use and criminal behaviour a sufficiently high dose of methadone (e.g., >60 mg) and the treatment duration lasting the entire period of imprisonment appear crucial. On the basis of the analysed results the authors recommend the provision of PMMT for individuals with long-standing opioid dependence and suggest major expansions of prison based ST in many countries.