“…While substitution therapy programs, high-and low-threshold, have shown very positive outcomes for opioid users (Farré, Mas, Torrens, Moreno, & Cami, 2002;Fareed, Vayalapalli, Casarella, Amar, & Drexler, 2010;Marsch, 1998) an analogous option for problematic cocaine users has yet to emerge. Opioid substitution treatment (OST) has no 4 direct effect on cocaine use, which in turn has a deleterious effect on treatment outcome for opioid dependence (Sullivan et al, 2010;Williamson, Darke, Ross, & Teeson, 2006).…”