Opioid commonly used

Brief experimentation with illicit opioids rarely leads to dependence, but persons who use opioids commonly escalate to daily use, at least once per month for at least a brief period. Among Vietnam War-era soldiers, experimentation with opioids was widespread 73% of the soldiers who used opioids at least five times became dependent however, 88% of enlisted men who became addicted to heroin did not become readdicted at any time in the 3 years after return, and 56% did not use opioids at all during that time (Robins et al. 1975). 

The IV or IM administration of parenteral narcotics (meperidine, morphine, fentanyl) is commonly used to treat the pain associated with labor. Compared to epidural analgesia, parenteral opioids are associated with lower rates of oxytocin augmentation, shorter stages of labor, and fewer instrumental deliveries. 

Like morphine, codeine is a naturally occurring opioid found in the poppy plant. Codeine is indicated for the treatment of mild to moderate pain and for its antitussive effects. It is widely used as an opioid antitussive because at antitussive doses it has few side effects and has excellent oral bioavailability. Codeine is metabolized in part to morphine, which is believed to account for its analgesic effect It is one of the most commonly used opioids in combination with nonopioids for the relief of pain. The administration of 30 mg of codeine in combination with aspirin is equivalent in analgesic effect to the administration of 65 mg of codeine. The combination of the drugs has the advantage of reducing the... 

L B. The most commonly used treatment and the most effective is to stabilize the patient with methadone and gradually reduce the maintenance dose until the patient is drug free. The administration of meperidine would reverse the abstinence syndrome but it is unlikely to help the patient terminate his opioid habit. The use of naltrexone would likely further precipitate the abstinence syndrome and without additional counseling, would not likely offer long-term beneht. 

It is generally accepted that three major classes of opioid receptors exist. The most commonly used terminology discriminates between p-, K-, and 8-opioid receptors. However, after cloning of the three genes encoding opioid receptors, a new nomenclature was agreed upon OPl (corresponding to the 8 receptor), OP2 (k receptor) and OP3 (p receptor) (Dhawan et ah. 

Finally, it should be stressed again that certainly not all benzodiazepine prescribing to opioid maintenance patients need be long term. McDuff et al. (1993) reported on detoxification from alprazolam, the benzodiazepine most commonly used by their methadone subjects. With methadone dosage usually remaining the same, patients were offered a set reducing course of alprazolam over 11 weeks. Of 22 patients, four refused the treatment and 12 out of 18 subsequently completed detoxification, although timescales in practice proved variable. In a comparative study by Weizman et al. (2003) just over a quarter of benzodiazepine-dependent methadone maintenance patients remained free of benzodiazepines... 

The opioid derivatives most commonly used as antitussives are dextromethorphan, codeine, levopropoxyphene, and noscapine (levopropoxyphene and noscapine are not available in the USA). They should be used with caution in patients taking monoamine oxidase inhibitors (see Table 31-5). Antitussive preparations usually also contain expectorants to thin and liquefy respiratory secretions. Importantly, due to increasing reports of death in young children taking dextromethorphan in formulations of over-the-counter "cold/cough" medications, its use in children less than 6 years of age has been banned by the FDA. Moreover, due to variations in the metabolism of codeine, its use for any purpose in young children is being reconsidered. 

Although opioids may have been the first drugs to be abused (preceding stimulants), they are still among the most commonly used for nonmedical purposes. 

Chen, Z.R., Irvine, R.J., Somogyi, A.A., Bochner, F. Mu receptor binding of some commonly used opioids and their metabolites. Life Sci. 1991, 48, 2165-2171. 

Frequently, a preoperative sedative is given to a patient 1 to 2 hours before the administration of general anesthesia.2,36 Sedatives are usually administered orally or by intramuscular injection, and are given while the patient is still in his or her room. This approach serves to relax the patient and reduce anxiety when arriving at the operating room. Commonly used preoperative sedatives include barbiturates (secobarbital, pentobarbital), opioids (butorphanol, meperidine), and benzodiazepines (diazepam, lorazepam) (Table 11-2). Different sedatives are selected depending on the patient, the type of general anesthesia used, and the preference of the physician. 

The amount of drug that is self-administered by the patient each time he or she activates the PCA delivery mechanism is known as the demand dose. The magnitude of these doses for some commonly used opioid analgesics is listed in Table 17-1. 

The minimum amount of time allowed between each demand dose is called the lockout interval. After the patient self-administers a dose, the PCA delivery system will not deliver the next dose until the lockout interval has expired. Typical lockout intervals for commonly used opioids are listed in Table 17-1. 

Side effects typically seen when opioids are used for PCA include sedation, pruritus, and gastrointestinal problems (nausea, vomiting). The incidence of these side effects, however, is not significantly increased during PCA versus more traditional methods of opioid administration such as intermittent intramuscular dosing.18 Respiratory depression is another common side effect of opioid use, but again, there is no increased incidence of this problem when appropriate amounts... 

Treatment will call upon dopamine agonists, opioid medications, a benzodiazepine (clonazepam) that increases total sleep time, and drugs most commonly used as antiepileptic medication, such as gabapentin or equivalent. Dopamine agonists are the most effective and reduce the sleep deprivation and the patients complaints. But not all patients respond to dopamine agonists and methadone has been prescribed in the most refractory cases (21). 

TABLE 1 Drugs Commonly Used to Examine the Relationship Between Delta Opioid Systems and Substance Abuse3... 

Opioids, NSAIDs, acetaminophen, and COX-2 inhibitors (all discussed in previous chapters) are the most commonly used pain relievers, but they do not relieve all types of pain. Neuropathic pain (also called neuropathy) and migraine headaches are for the most part unaffected by these pain relievers, so different medications are used to treat these conditions. 

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