The aim of this report is to summarize available evidence on the effectiveness and cost- effectiveness of needle exchange programs to reduce harm associated with injection drug use in prisons, to facilitate the evaluation of the benefits of the program in correctional settings. [...] Summary of Critical Appraisal The strengths and limitations of the individual studies are summarized and presented in Appendix 3. It is unknown whether the included studies were planned a priori or they were post hoc evaluations following the implementation of the needle exchange programs in the various reasons. [...] The study also found a decrease in the rate of abscesses among IDUs during the exchange program, and reported that the general mood of female prisoner had improved along with their weight and other laboratory values.1 Three of the studies1,3,8 reported that evidence of harm related to the needle/syringe exchange program in prisons such as an overall increase in injection drug use, or violence invo [...] Therefore, in the absence of a control group, it is The investigators had no conflicting interests not possible to conclude that the outcomes of the study were solely due to which could be a source of potential bias in the the provision of sterile injection equipment, since the impact of intensified study. [...] Summary of Findings of Included Studies Main Study Findings Author's Conclusions Ferrer-Castro, 20127 There was a significant decreased in the prevalence of HIV "After ten years of development of the NEP, there was a and HCV at the 10-year follow-up (from 21% and 40% at significant decrease in the prevalence of HIV and HCV in the baseline to 8.5% and 26.1%, respectively; P