Opioid analgesics adverse effects

In a randomized, placebo-controlled study in 60 patients given dextromethorphan 10, 20, or 40 mg intramuscularly before abdominal surgery, there was a dose-dependent effective postoperative analgesic effect, with lower total consumption of rescue morphine during the 3-day observation period (6). There were no opioid-related adverse effects in those who were given dextromethorphan 40 mg. 

In a retrospective review of 37 patients with chronic non-malignant pain (mostly from failed lumbosacral spine surgery) treated with intrathecal hydromorphone there was an analgesic response in six of the 16 patients who were switched from morphine to hydromorphone because of poor pain relief (1). Opioid-related adverse effects, such as nausea, vomiting, pruritus, and sedation, were also reduced by hydromorphone in the 21 patients who were switched to hydromorphone because of morphine-related adverse effects, especially 1 month after use. These results should be treated cautiously, because of the limitations of a retrospective study that lacks strict inclusion criteria, with obvious population bias and under-reporting, and without standardized procedures for rotation to hydromorphone. 

In a prospective, open, uncontrolled study 50 patients with a history of cancer taking daily oral morphine (90-800 mg) but with uncontrolled pain with or without severe opioid adverse effects were switched to oral 8-hourly methadone in a dose ratio of 1 4 for patients receiving less than 90 mg of morphine daily, 1 8 for patients receiving 90-300 mg daily, and 1 12 for patients receiving more than 300 mg daily (5). Methadone was effective in 80% of the patients when comparing analgesic response with opioid-related adverse effects. Ten patients were switched because of uncontrolled pain, eight because of moderate or severe adverse effects in the presence of acceptable pain control, and 32 because of uncontrolled pain with morphine-related adverse effects. 

Epidural analgesia is frequently used for lower extremity procedures and pain (e.g., knee surgery, labor pain, and some abdominal procedures). Intermittent bolus or continuous infusion of preservative-free opioids (morphine, hydromorphone, or fentanyl) and local anesthetics (bupivacaine) may be used for epidural analgesia. Opiates given by this route may cause pruritus that is relieved by naloxone. Adverse effects including respiratory depression, hypotension, and urinary retention may occur. When epidural routes are used in narcotic-dependent patients, systemic analgesics must also be used to prevent withdrawal since the opioid is not absorbed and remains in the epidural space. Doses of opioids used in epidural analgesia are 10 times less than intravenous doses, and intrathecal doses are 10 times less than epidural doses (i.e., 10 mg of IV morphine is equivalent to 1 mg epidural morphine and 0.1 mg of intrathecally administered morphine).45... 

Opioid rotation is the switch from one opioid to another to achieve a better balance between analgesia and treatment-limiting adverse effects. This practice is often used when escalating doses (greater than 1 g of morphine per day) become ineffective. In some settings opioid rotation is utilized routinely to prevent the development of analgesic tolerance.48... 

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. 

For a patient in severe pain, the administration of an opioid analgesic is usually considered a primary part of the overall management plan. Determining the route of administration (oral, parenteral, neuraxial), duration of drug action, ceiling effect (maximal intrinsic activity), duration of therapy, potential for adverse effects, and the patient s past experience with opioids all should be addressed. One of the principal errors made by physicians in this setting is failure to adequately assess a patient s pain and to match its severity with an appropriate level of therapy. Just as important is the principle that following delivery of the therapeutic plan, its effectiveness must be reevaluated and the plan modified, if necessary, if the response was excessive or inadequate. 

Because of their direct action on the superficial neurons of the spinal cord dorsal horn, opioids can also be used as regional analgesics by administration into the epidural or subarachnoid spaces of the spinal column. A number of studies have demonstrated that long-lasting analgesia with minimal adverse effects can be achieved by epidural administration of... 

Efficacy and clinical use Naltrexone (Crabtree, 1984 Gonzalez and Brogden, 1988) is a pure opioid antagonist and has no analgesic activity. It is used for the treatment of opioid adverse effects, for opioid detoxification and as maintenance treatment for former addicts to avoid a relapse. In chronic opioid users, naltrexone may precipitate an acute withdrawal reaction. 

Even the most severe acute pain (that lasting hours to days) can usually be well controlled—with significant but tolerable adverse effects—with currently available analgesics, especially the opioids. Chronic pain (lasting weeks to months), however, is not very satisfactorily managed with opioids. It is now known that in chronic pain, presynaptic receptors on sensory nerve terminals in the periphery contribute to increased excitability of sensory nerve endings (peripheral sensitization). 

Alfentanil Hydrochloride Alfentanil hydrochloride can cause drug dependence similar to that of opioid analgesics. Since this may cause irritation and related adverse effects, it is important to avoid skin contact and the inhalation of alfentanil hydrochloride particles to contain adverse effects. 

Fentanyl and its analogs are drugs of abuse. Overdose and dependence may lead to respiratory complications and death.58 Adverse effects can be treated with drugs such as naloxone, atropine, and neuromuscular blockers. In general, interactions are similar to those of opioid analgesics. 

Pentozocine Lactate Injections of pentozocine lactate are incompatible with sodium bicarbonate, barbiturates, diazepam, chlordiazepoxide, glycopyrronium bromide, and nafcillin sodium. Dependence, withdrawal, and treatment of adverse effects are generally similar to those of opioid analgesics. 

Dependence, withdrawal, and treatment of adverse effects are similar to those of opioid analgesics, and synthetic analogs are abused. 

Yes. Although stimulant laxatives are often considered to be second line, it has been said that laxative choice is best based on symptoms, patients preference, adverse effects and cost. In the case of Mr A the stimulant laxatives have the advantage of being fairly quick acting, and are often useful to counteract the effects of decreased bowel motility caused by opioid analgesics. They are also useful for occasional use. 

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