Suboxone is a medicine made from two medications, buprenorphine and naloxone.
The buprenorphine is the active ingredient. The naloxone is a blocking agent that is present only to prevent IV injection of Suboxone. When used under the tongue as directed, almost no naloxone is absorbed.
The various doses of Suboxone have two numbers such as 8/2, 4/1 and 2/.5, with the first representing the number of milligrams of Suboxone and the second number representing the number of milligrams of naloxone. Suboxone is available only as a sublingual film which is very easy and fast to be absorbed when taken properly.
Subutex® is no longer made, but was the pure buprenorphine product from the manufacturers of Suboxone. It was designed for people who cannot tolerate naloxone or pregnant women.
Buprenorphine is available in generic form from many suppliers. Unfortunately, experience suggests that it is less effective than brand Suboxone because it is not absorbed as well as Suboxone and thus even though it starts out with the same amount of medication, as little as 60% of the original medication makes it to the brain compared to Suboxone.
There is another branded version of Suboxone, called Zubsolv, although available only by pill and not by film. It is not clear if it is comparable to Suboxone. There is also a generic version, but it is too new to judge its efficacy.