Thebaine

Thebaine (paramorphine), also known as codeine methyl enol ether, is an opiate alkaloid, its name coming from the Greek Θῆβαι, Thēbai (Thebes), an ancient city in Upper Egypt. A minor constituent of opium, thebaine is chemically similar to both morphine and codeine, but has stimulatory rather than depressant effects. At high doses, it causes convulsions similar to strychnine poisoning. The synthetic enantiomer (+)-thebaine does show analgesic effects apparently mediated through opioid receptors, unlike the inactive natural enantiomer (−)-thebaine. While thebaine is not used therapeutically, it is the main alkaloid extracted from Papaver bracteatum (Iranian poppy) and can be converted industrially into a variety of compounds, including oxycodone, oxymorphone, nalbuphine, naloxone, naltrexone, buprenorphine and etorphine. Butorphanol can also be derived from thebaine and is scheduled separately from butorphanol derived by other processes.

Thebaine is controlled under international law, is listed as a Class A drug under the Misuse of Drugs Act 1971 in the United Kingdom, is controlled as an analog of a Schedule II drug per the Analog Act in the United States, and is controlled with its derivatives and salts, as a Schedule I substance of the Controlled Drugs and Substances Act in Canada. The 2013 US Drug Enforcement Administration (DEA) aggregate manufacturing quota for thebaine (ACSCN 9333) was unchanged from the previous year at 145 metric tons.

This alkaloid is biosynthetically related to salutaridine, oripavine, morphine and reticuline.

In 2012 146,000 kilograms of thebaine were produced. In 2013, Australia was the main producer of poppy straw rich in thebaine, followed by Spain and then France. Together, those three countries accounted for about 99 per cent of global production of such poppy straw.