A minor constituent of opium, thebaine is chemically similar to both morphine and codeine, but produces stimulatory rather than depressant effects. Thebaine is not used therapeutically, but is converted into a variety of compounds including codeine, hydrocodone, oxycodone, oxymorphone, nalbuphine, naloxone, naltrexone, and buprenorphine. It is controlled in Schedule II of the Controlled Substances Act as well as under international law.