Opioids codeine

Opioids Codeine + + Same as opioid ag- Same as opioid ago- ... 

Suppression of the cough reflex is a well-recognized action of opioids. Codeine in particular has been used to advantage in persons suffering from pathologic cough and in patients in whom it is necessary to maintain ventilation via an endotracheal tube. However, cough suppression by opioids may allow accumulation of secretions and thus lead to airway obstruction and atelectasis. 

This chapter concentrates on some drug choices in acute rather than chronic pain, but the same principles can be used to determine the appropriateness of other types of analgesic. The drugs considered in this section are paracetamol, non-steroidal anti-inflammatories (NSAIDs specifically diclofenac, ibuprofen, indometacin, naproxen, sulindac and tenoxicam) and opioids (codeine, dihydrocodeine, morphine, pethidine and tramadol). Unless otherwise stated, all pharmacokinetic data originate from standard reference sources [1-5] and apply to adults only. 

Colitis may result from various gut infections, especially amoebic colitis. Clindamycin, vancon cin or metronidazole may be used in treatment. The diarrhoea of colitis states may be treated with normal ANTIDIARRHOEALS, e.g. the opioids codeine, morphine, diphenoxylate and loperamide. The colic may respond to ANTISPASMODICS, e.g. the anticholinergics atropine, hyoscine, dicyclomine, propantheline. Meheverine is a direct-acting antispasmodic effective in some types of gut colic. 

Morphine is the prototype of the strong opioids. Meperidine is a variant used commonly for analgesia. Methadone is a strong agonist used in maintenance programs for patients addicted to opioids. Codeine, oxycodone, and hydrocodone are moderate agonists, whereas propoxyphene is a weak agonist. 

Fluoxetine inhibits the activity of the cytochrome P450 isoenzyme CYP2D6 within the liver so that the metabolism of oxycodone to an aetive metabolite oxymorphone is reduced. The metabolism of hydroeodone and similar opioids may also be affected by CYP2D6 inhibitors, see Opioids Codeine and related drugs + Quinidine , p.l84. Buprenorphine and morphine are not metabolised by CYP2D6, so their metabolism would not be expeeted to be affected by fluoxetine. Buprenorphine is metabolised by CYP3A4 and so fluvoxamine might be expected to inhibit its metabolism to some extent. 

Morphine group (phenanthrenes, opioids) Codeine, morphine, narcotoline, neopine, perparin, papaverrubine D (porphyroxine), pseudocodeine, pseudomorphine, thebaine... 

In the strict sense, opiates are drugs which are derived from opium and include the natural products morphine, codeine, thebaine and many semi-synthetic congeners derived from them. In the wider sense, opiates are morphine-like drugs with non-peptidic structures. The old term opiates is now more and more replaced by the term opioids which applies to any substance, whether endogenous or synthetic, pqrtidic or non-peptidic, that produces morphine-like effects through an action on opioid receptors. 

Tramadol is a pain reliever (analgesic). Its action is similar to opioid narcotics such as codeine and morphine, but it does not depress breathing the way the others can, and less often leads to abuse and addiction. 

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. 

Opioids. Reactions to morphine, codeine phosphate, meperidine, fentanyl and its derivatives are uncommon. Because of their direct histamine-releasing properties, especially regarding morphine and codeine, distinction between anaphylaxis and non-immune-mediated histamine release is not always easy. Only 12 cases were recorded in the last 2 years epidemiologic survey in France, 9 of them being related to morphine administration [9]. 

Moderate 4-6/1 0 Add an opioid to the non-opioid for moderate pain regular scheduled dosing Acetaminophen 325 mg + codeine 60 mg every 4 hours Acetaminophen 325 mg + oxycodone 5 mg every 4 hours Consider step-up therapy if pain is not relieved by greater than or equal to 2 or more different drugs... 

Few studies have explored the efficacy of opioids specifically for OA. The APS recommends against the use of codeine and propoxyphene for OA because of the high incidence of adverse effects and limited analgesic effectiveness. Oxycodone is the most extensively studied of the agents recommended for OA. However, other narcotic analgesics such as morphine, hydromorphone, methadone, and transdermal fentanyl are also effective. 

Severe pain should be treated with an opioid such as morphine, hydromorphone, methadone, or fentanyl. Moderate pain can be treated effectively in most cases with a weak opioid such as codeine or hydrocodone, usually in combination with acetaminophen. Meperidine should be avoided owing to its relatively short analgesic effect and its toxic metabolite, normeperidine. Normeperidine may accumulate with repeated dosing and can lead to central nervous system side effects including seizures. 

When Montgomery and I published our article, we thought we had disproven another theory of placebo effects - the theory that placebo effects are produced by the release of endorphins in the brain. In 1978 researchers at the University of California in San Francisco discovered that when placebos reduce pain, they may stimulate the release of endorphins.18 Endorphins, the existence of which had only been discovered a few years earlier, are opioids that are produced naturally by the brain. Just like the opiates that are derived from opium - morphine and codeine, for example - endorphins reduce the sensation of pain. The University of California researchers reasoned that if placebos can mimic the effects of opiate drugs, maybe they do so by stimulating the release of the brain s endogenous opioids. 

The answer is c. (Hardman, pp 528-537.) Morphine is a pure agonist opioid drug with agonist activity toward all the opioid subtype receptor sites. In high doses, deaths associated with morphine are related to the depression of the respiratory center in the medulla. Morphine has a high addiction potential related to the activity of heroin or dihydromorphine. Codeine has a significantly lower addiction potential. 

In the case of heroin, the indicator used is nonexclusive of heroin consumption, as it is also excreted to a high extent after administration of therapeutic morphine and in minor proportions after use of other opioids, such as codeine, pholcodine, and ethylmorphine. In order to obtain comparable results to previous studies [25, 31], an average medical administration of morphine of 10 mg/capita/year [45] and an excretion rate of 85% of morphine after therapeutic use [25, 31] were considered in the calculations. 

Wilcox, R.A. and Owen, H. (2000) Variable cytochrome P450 2D6 expression and metabolism of codeine and other opioid prodrugs implications for the Australian anaesthetist. Anaesthesia and Intensive Care, 28 (6), 611-619. 

---