Codeine drug class

The term opioid refers to any exogenous substance that acts as an agonist at any of several receptors. Opioid antagonists are drugs that bind to a receptor but produce no actions. The poppy plant, Papaver somniferum, from which opium is obtained, is grown in many areas of the world. Morphine constitutes 10% of opium, and codeine can be obtained direcdy from opium. Semisynthetic opioids such as heroin and oxycodone are obtained directly or indirectly from morphine. There are other distinct chemical classes of drugs with opioid actions, including the methadones. 

Among the compounds that fall within this class are hydrocodone (e.g., Vicodin), oxycodone (e.g., OxyContin—an oral, controlled-release form of the drug), morphine, fentanyl, codeine, and related medications. Morphine and fentanyl are often used to alleviate severe pain, while codeine is used for milder pain. Other examples of opioids prescribed to relieve pain include propoxyphene (Darvon) hydromorphone (Dilaudid) and meperidine (Demerol), which is used less often because of its side effects. In addition to their effective pain-relieving properties, some of these medications can be used to relieve severe diarrhea (for example, Lomotil, also known as diphenoxylate) or severe coughs (codeine). 

Members of the group of natural, semisynthetic, or synthetic alkaloid compounds prepared from opium are referred to as opioids. This group includes natural compounds usually denoted opiates, such as morphine and codeine, and the synthetic and semi synthetic compounds such as oxycodone, buprenorphine, fentanyl, methadone, and tramadol. The pharmacological effects and pharmacokinetic parameters of these drugs share many common characteristics and are illustrated with the prototypic drug in this class, morphine. 

Morphine is an alkaloid, the chemical class to which many drugs belong. Pure morphine is a white powder, bitter to the taste. More than 1,000 tons of morphine are isolated from opium a year, although most of it is converted to codeine. Morphine comprises anywhere from 3% to 17%—usually about 10%—of the more than 20 alkaloids present in opium. 

Figure 8.2 Multiwavelength and single-wavelength (195 nm) MEKC electrophero-grams obtained with the fractions of a two-step extraction of a patient sample, which tested positively for several classes of drugs. Peaks 1, benzoylecgonine 2, morphine 5, codeine 9, methaqualone 13, 6-MAM.

In the United Kingdom, diamorphine is controlled as a Class A drng, nnder Part 1 of Schednle 2 of the Misnse of Drugs Act, 1971, as is its precursor, morphine. Codeine is controlled as a Class B drug. In addition, the prodncts fonnd as imparities from diamorphine prodnction, namely 3-monoacetyhnorphine and 6-monoacetylmorphine, are controlled as esters of morphine, while acetylcodeine is controlled as an ester of codeine. In the United States, heroin (diamorphine) is controlled as a Schednle I narcotic. 

The opioid drugs are responsible for more reported cases of renal damage than any other class of abused drug. While opioids include morphine, codeine, methadone, meperidine, and other agents, most cases of renal damage are related to heroin abuse. Heroin is derived from the acetylation of morphine at two-sites and is rapidly absorbed from all mucous membranes and the lungs. 

Among opioids, morphinans (Fig. 1) play an important role as therapeutically valuable drugs. Representative examples of the morphinan class of compounds (Fig. 2) are p-opioid analgesic agents for the treatment of moderate-to-severe pain such as naturally occurring alkaloids (e.g. morphine, codeine), semisynthetic derivatives (e.g. oxycodone, oxymorphone, buprenorphine), and synthetic analogs (e.g. levorphanol, butorphanol) [19-21], Codeine is also an effective antitussive drug. The oxymorphone derivatives naloxone [22] and naltrexone [23] represent... 

Morphine and related drugs possessing potent narcotic analgesic properties, are used in clinical practice. A few examples belonging to this class of compounds are morphine sulphate diamorphine hydrochloride codeine dihydrocodeine phosphate hydromorphone hydrochloride hydrocodone tartrate oxymorphone hydrochloride. 

Codeine for furriier details. Cited in Lombardo F, Obach RS, Shalaeva MY and Gao F, Prediction of human volume of distribution values for neutral and basic drugs. 2. Extended data set and leave-class-out statistics, /. Med. Chem., 47,1242-1250 (2004) (ref. 285). 

Spectra in the mid-infrared range were recorded in 70 blood serum samples representing seven classes of the drugs codeine, methamphetamine, desmethyldiazepam, oxazepam, diazepam, amphetamine sulfate, and hydromorphone. For data analysis, the absorbances at 16 wavenumbers were chosen as input to the CART algorithm. The resulting classification tree has the following shape ... 

The opium poppy (Papaver somniferum L. [Papaveraceae]) latex contains benzylisoquinoline alkaloids and is a widely known source of the analgesic drugs morphine and codeine. The biosynthesis of benzylisoquinoline alkaloids begins with a condensation reaction catalyzed by norcoclaurine synthase of DA [161]. The structural features of benzylisoquinoline alkaloids derived from DA might provide some explanation for the documented affinity of some natural alkaloids of this class, and some synthetic derivatives, for DA receptors [162]. Indeed, the chemical structure of morphine has been used as a template for the development of the PD drug, apomorphine (47). Apomorphine includes a catecholaminergic moiety in its... 

The class of narcotic drugs encompasses the opium-derived drugs of morphine, heroin, and codeine (Figure 16.1) as well as other narcotics, such as meperidine, hydromorphone, hydrocodone, and the fentanyl compounds. Because these are highly polar compounds and often require high temperatures for elution, GC is difficult and often demands derivatization. Morphine, for example, because of its amphoteric nature, is not only difficult to extract but must be derivatized to obtain good quantitative data. 

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