Main Page | See live article | Alphabetical index Opiates are a class of drugs that are derivatives (in the broadest sense of the word) of opium. These include two groups of alkaloids: phenanthrenes and papaverines. Opiates in the narrower sense of the word are only the phenanthrenes. Opioids are synthetic drugs that are chemically unrelated to the opiates, but act on the same receptors in the central nervous system and have similar clinical effects. Phenanthrenes: Naturally occurring in opium: Morphine Codeine Semisynthetic derivatives: Heroin Hydromorphone Oxymorphone Hydrocodone Oxycodone Fully synthetic: Phenylheptylamines: Methadone levomethadyl acetate hydrochloride (LAAM) Phenylpiperidines: Meperidine Fentanyl Alfentanil Sufentanil Remifentanil Veterinary: Etorphine Carfentanyl A high number of opiates are considered to be highly addictive. One exception is loperamide, which cannot cross the blood-brain barrier. See also: opioid analgesic, nootropics. Opiate is an EP by Tool, an American rock band formed in 1989. See Opiate (album) Opiate is also the name of a rock-metal band based in the United Kingdom and signed to Visible Noise records, home of lost prophets. See Opiate (band). This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.