Opioid drugs

Opioid drugs are often more effective than other nonnarcotic treatments, but they are also associated with more side effects making them less suitable for many patients. Higher doses which are more effective are also associated with undesirable effects such as sedation. 

Cheskin LJ, Fudala PJ, Johnson RE A controlled comparison of buprenorphine and clonidine for acute detoxification from opioids. Drug Alcohol Depend 36 115-121, 1994... 

Morphine acts on the mu receptor, and so do most of the clinically used opioid drugs. The detailed structure of these receptors has been described and we now have a reasonable understanding of their relative roles in physiological functions and in different pain states. 

There is little new with regard to the mu receptor, the main target for opioid drugs. The receptor is remarkably similar in structure and function in all species studied so animal studies will be good predictors for clinical applications. Although there have been suggestions of subtypes of the receptor, the cloned mu receptors have all been identical. 

The mu, kappa, and delta opioid receptors have been found to interact with endogenous peptide ligands that share certain pharmacologic properties with opioid drugs. These peptide ligands are derived from at least three different prohormones located in both... 

Delta receptors are relatively selective for two related penta-peptides, methionine enkephalin and leucine enkephalin (met- and leu-enkephalin), which were isolated from porcine brain (Hughes 1975). Both met- and leu-enkephalin inhibit electrically induced contractions of guinea pig ileum, an effect that mimics those effects seen with opioid drugs, and is naloxone reversible. The enkephalins are processed posttranslational ly from proenkephalin, and secreted from central and peripheral neurons and endocrine cells in the adrenal medulla. 

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. 

Immunochemical methods have been reported for the determination of these substances in body fluids (see Table 8) in clinical and forensic analyses. In the case of illicit use of opioid drugs, methods have also been reported for the control of drug abuse and assessment of intoxication using body fluids, tissue extracts, post-mortem specimens, and seizure samples. For this reason there are several commercially available immunochemical methods (see Table 4). 

Tolerance and dependence are characteristic of repeated administration of opioid drugs, which limits their use in treatment. It has been proposed that tolerance results from desensitization of opioid receptors and altered... 

The chemical structures and biological activities of hundreds of opioid analgesics derived from the prototype opioid drug morphine are most comprehensively described in two books published in 1986, one entitled Opioid Analgesics, Chemistry and Receptors by Casy and Parfitt [1] and the other entitled Opiates by Lenz et al. [2]. Follow-up articles include those by Casy in 1989, entitled Opioid Receptors and their Ligands Recent Developments [3] which also includes sections on opioid peptides, affinity labelling and opioid receptor subtypes Rees and Hunter in 1990 [4] covering the... 

To show how fast memories fade, 1 recently contacted Ted Stanley after finding out by surfing the Net that he was an expert on the opioid drugs. 1 wanted to get his ideas about the gas used in the Moscow incident. We had pleasant conversations on the phone, but neither of us remembered the other. 

Consequently the opioid drugs (e.g. codeine, morphine), which are normally used to control pain, can cause constipation. 

Voltarol is a brand-name preparation for diclofenac (NSAID) and modified-release tablets are available in 75 mg and 100 mg strength. Nu-seals is a proprietary preparation of enteric-coated aspirin 75 mg. Fentanyl, co-codamol and Suboxone (buprenorphine and naloxone) consist of opioid drugs. 

Therefore, dietetic and pharmacological measures should be taken prophylacti-cally to prevent constipation, whenever prolonged administration of opioid drugs is indicated. 

Reversal of opioid effects Complete or partial reversal of opioid drug effects, including respiratory depression, induced by either natural or synthetic opioids. Opioid overdose Management of known or suspected opioid overdose. 

Discontinue all other around-the-clock opioid drugs when CR tablet therapy is initiated. 

Mechanism of Action An opioid agonist that binds with opioid receptors in the CNS. Therapeutic Effect Alters the perception of and emotional response to pain reduces withdrawal symptoms from other opioid drugs. 

Antimotility drugs are opioid drugs. They increase small bowel smooth muscle tone and segmentation activity. They also reduce propulsive movements and decrease intestinal secretions while increasing absorption. They mediate these actions through p receptors. 

Castells X, Casas M, Vildal X, Bosch R, Roncero C, Ramos-Quiroga JA Capella D (2007) Efficacy of central nervous system stimulant treatment for cocaine dependence a systematic review and meta-analysis of randomized controlled clinical trials. Addiction, 102, 1871-87 Chaisson RE, Bacchetti P, Osmond D, Brodie B, Sande MA Moss AR (1989). Cocaine use and HIV infection in intravenous drug users in San Francisco. Journal of the American Medical Association, 261, 561-5 Chapleo CB Walter DS (1997). The bupre-norphine-naloxone combination product. Research and Clinical Forums, 19, 55-8 Cheskin LJ, Fudala PJ Johnson RE (1994). A controlled comparison of buprenorphine and clonidine for acute detoxification from opioids. Drug and Alcohol Dependence, 36, 115-21... 

The treatment of constipation and questions of use and abuse of laxatives are not normally of major interest to the anaesthetist. However, constipation is a particular problem in terminal care patients, especially where they are receiving opioid drugs for pain relief, and its prevention and management must be an integral part of their treatment. Both constipation and diarrhoea are problems in the intensive care patient. 

Chiorphenamine is effective in reducing pruritus from opioid drugs and may have synergistic activity with other anti-emetic drugs, although it is not primarily used as an anti-emetic. 

Use of opioid drugs in acute situations may be contrasted with their use in chronic pain management, in which a multitude of other factors must be considered, including the development of tolerance to and physical dependence on opioid analgesics. 

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