Opiate pain relievers analgesia

Table 3.1 on pages 44-45 lists commonly used opiate pain relievers. All opiates require a doctor s prescription. The medications differ primarily by their duration of action and the dose required to obtain sufficient analgesia. 

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... 

Delta receptor activation also produces analgesia, but it can also cause seizures as well. Delta receptors normally bind to a class of endogenous ligands known as enkephalins, but unlike mu receptors, information about delta receptors is limited. Enkephalins are peptides that are produced by the pituitary gland. Several different enkephalins have been identified. [3-Enkephalin resembles opiates because when it binds to a delta receptor, it relieves pain.11... 

Oxycodone hydrochloride/aspirin is an opioid analgesic combination. Oxycodone relieves pain by stimulating opiate receptors in CNS. Aspirin inhibits prostaglandin synthesis, resulting in analgesia, antiinflammatory activity, and inhibition of platelet aggregation. It is indicated for the relief of moderate to moderately severe pain. 

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