Subutex is buprenorphine without naloxone. It is available here (in the U.S.) and only used for specific cases where a relapse or abuse of Suboxone would cause more harm than good (such as with pregnant women). Research shows that with heroin and other opiates, relapse is over 80% likely when not taking a replacement medication. Addicts lose their tolerance while off the drugs, cold turkey, which is why many of them OD when relapsing. They try to start back on the dose they last used. There may be individual cases of "cold turkey" and rapid detoxes, etc that were successful, but they aren't supported by science, which is what the medical community relies on.