Buprenorphine is an opioid drug with partial agonist and antagonist actions. Buprenorphine hydrochloride was first marketed in the 1980s by Reckitt & Colman (now Reckitt Benckiser) as an analgesic, available generally as Temgesic 0.2 mg sublingual tablets, and as Buprenex in a 0.3 mg/ml injectable formulation. In October 2002, the Food and Drug Administration (FDA) of the United States of America additionally approved Suboxone and Subutex, buprenorphine's high-dose sublingual pill preparations for opioid addiction, and as such the drug is now also used for this purpose. In the USA, it has been a Schedule III drug under the United Nations' Convention on Psychotropic Substances since it was rescheduled from Schedule V (the schedule with the lowest restrictions and penalties in the USA) just before FDA approval of Suboxone and Subutex. In the recent years, buprenorphine has been introduced in most European countries as a transdermal formulation ("patch") for the treatment of chronic pain.