Codeine Hydrocodone

Codeine, hydrocodone, morphine, methadone, and oxycodone are substrates of the cytochrome P-450 isoenzyme CYP2D6.47 Inhibition of CYP2D6 results in decreased analgesia of codeine and hydrocodone due to decreased conversion to the active metabolites (e.g., morphine and hydromorphone, respectively) and increased effects of morphine, methadone, and oxycodone. Methadone is also a substrate of CYP3A4, and its metabolism is increased by phenytoin and decreased by cimetidine. CNS depressants may potentiate the sedative effects of opiates. 

Hydrocodone Hydrocodone, 4,5-epoxy-3-methoxy-Af-methyl-6-oxomorphinane (3.1.27), is a compound that is chemically related to morphine and codeine. Hydrocodone is synthesized by the isomerization of codeine (3.1.20) using a palladium or platinum catalyst [18]. This drug has also been suggested to be synthesized by the hydration of codeinone [19] and by oxidation of dihydrocodeine [20]. 

Hydrocodone is a widely prescribed (and abused) pharmaceutical designed as a pain-reliever. The drug works by converting into a form of morphine once it enters the body. Hydrocodone can be derived from either codeine or thebaine and is three times more powerfiil than codeine. Hydrocodone has various trade names. 

Dahn T, Gunn J, Kriger S, Terrell AR (2010) Quantitation of morphine, codeine, hydrocodone, hydromorphone, oxycodone, oxymorphone, and 6-monoacetylmorphine (6-MAM) in urine, blood, serum, or plasma using liquid chromatography with tandem mass spectrometry detection. Methods Mol Biol 603 411 122... 

Codeine, hydrocodone, and hydromorphone decrease the sensitivity of CNS cough centers to peripheral stimuli, and decrease mucosal secretion. These actions occur at doses lower than required for analgesia (see p. 135 for a more complete discussion of the opiates). Dextromethorphan [dex troe meth OR fan], a synthetic derivative of morphine, suppresses the response of the cough center. It has no analgesic or addictive potential, and is less constipating than codeine. 

Prototypical agent Motphine, a naturally occurring opioid, is derived from the poppy plant. Other natural, semisynthetic and synthetic opioids include codeine, hydrocodone, oxycodone, methadone, fentanyl, and hydrofflorphone, among others. 

Codeine, hydrocodone, and hydromorphone are used in combination products as antitussives. "M be beneficial in vascular headaches. 

A number of drugs of abuse are known substrates (e.g., codeine, hydrocodone, p-methoxyamphetamine, amphetamine) or inhibitors (e g., (-)-cocaine, pentazocine) of CYP2D6. For some of these drugs, the pharmacokinetic differences due to the polymorphism will be so profound that they are likely to exceed pharmacodynamic sources of variation in response. For other drugs (e.g., hydrocodone to hydromorphone, codeine to morphine, oxycodone to oxymorphone), CYP2D6 may not contribute importantly to the overall clearance of the drug, but may catalyze the formation of highly active metabolites. 

Weak opioids (e.g., codeine, hydrocodone, oxycodone) often are combined with... 

Alvi, S.U. Castro, F. A stability-indicating simultaneous analysis of acetaminophen and hydrocodone bitartrate in tablets formulation by HPLC. J.Liq.Chromatogr., 1987, 10, 3413-3426 [stability-indicating simultaneous codeine, hydrocodone hydromorphone tablets column temp 30]... 

Importantly, the narcotic analgesic agents (see Chapter 11) retained an almost comfortable status in this are upto the recent times, such as morphine, hydromorphone, codeine, hydrocodone, methadone and levorphanol. 

Hydrocodone bitartrate is approximately threefold more effective on a weight basis as an oral antitussive medication compared to codeine. Hydrocodone also has greater analgesic activity and abuse potential than codeine. Hydrocodone is only available as a Schedule III prescription agent in combination formulations for cough suppression. 

Methadone is frequently used to treat heroin, codeine, hydrocodone, oxycodone, and morphine addictions. Methadone when used as prescribed, is safe and effective and does not cause euphoric sensations but does relieve physical withdrawal symptoms and reduces physiologic cravings. Methadone does have side effects which may be intolerable to some patients. They include constipation, water retention, drowsiness, skin rash, excessive sweating, and change in sex drive. Methadone has been used successfully in the treatment of opioid addiction for over 30 years. 

Hydrocodone (trade name in Germany Dicoditfl, though marketing approval has been withdrawn due to addiction risk) is an opioid as well, with a pharmacology that is comparable to codeine. Particularly pronounced is its antitussive activity. Hydrocodone has higher potency than codeine, and is therefore used for moderate to severe pain. It is formed by palladium- or platinum-catalysed double bond isomerisation of codeine. Hydrocodone production has seen an almost constant upward trend over the past 20 years, teaching 56 tonnes in 2011. It is exclusively manufactured in the United States, where it is used in combination products, e.g. with acetaminophen in Vicodin . [82]... 

While primarily employed as an analgesic, hydromor-phone is an excellent cough suppressant and is associated with less histamine release and pruritus than codeine. Hydrocodone is only available for oral administration, as either a tablet, capsule, or syrup formulation, and is usually combined with acetaminophen or ibuprofen. Standard immediate-release tablets provide 4-6 h of analgesia for patients with... 

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