Both Subutex and Suboxone contain the drug buprenorphine and are approved by the FDA to treat opioid addiction. The primary difference between the two is that Subutex only contains buprenorphine and Suboxone contains both buprenorphine and naloxone. Subutex was also formulated first, but users had a tendency to abuse it by injecting it. Suboxone was created with the intention to limit this abuse, as injecting it will cause immediate withdrawal effects which can be very unpleasant.