Opiates are alkaloid compounds naturally found in the opium poppy plant Papaver somniferum. The psychoactive compounds found in the opium plant include morphine, codeine, and thebaine. The term opiate should be differentiated from the broader term opioid, which includes all drugs with morphine-like effects, including opiates, semi-synthetic opioids derived from opiates (such as heroin, hydrocodone, hydromorphone, oxycodone, and oxymorphone), and synthetic opioids which are not derived from opiates (such as fentanyl, buprenorphine, and methadone). All opioids, including the opiates, are considered drugs of high abuse potential and are listed on various "Substance-Control Schedules" under the Uniform Controlled Substances Act of the United States.
In 2013 between 13 and 20 million people used opiates recreationally (0.3% to 0.4% of the global population between the ages of 15 and 65).
Opiates belong to the large biosynthetic group of benzylisoquinoline alkaloids, and are so named because they are naturally occurring alkaloids found in the opium poppy. The major psychoactive opiates are morphine, codeine, and thebaine. Papaverine, noscapine, and approximately 24 other alkaloids are also present in opium but have little to no effect on the human central nervous system, and as such are not considered to be opiates. Very small quantities of hydrocodone and hydromorphone are detected in assays of opium on rare occasions; it appears to be produced by the plant under circumstances and by processes which are not understood at this time and may include the action of bacteria.Dihydrocodeine, oxymorphol, oxycodone, oxymorphone, metopon and possibly other derivatives of morphine and/or hydromorphone also are found in trace amounts in opium.