The nonopioid analgesics are generally thought to prod analgesia inhibiting activation of peripheral nociceptive through their prevention of the formation of pros a known sensitizer of peripheral receptors to no population from tissue injury. The differ from one other both in duration of their analgesic action and in the pharmacokinetic profile. Ibuprofen and fenoprofen have short half-lives and the same duration of as aspirin, whereas diflunisal and naproxen have longer half-lives and longer acting. Because clinical experience has found some patients respond better to one NSAID than to another each patient should be given an adequate trial of one drug on a regular basis before switching to another. Survey data the WHO demonstration projects suggest that 20% to 40 of patients obtain pain relief with the use of nonopioid anagesice a alone.
These drugs are thought to have a special role to pay management of bone pain because numerous studies ha e shown that aspirin inhibits tumor growth in an animal model of metastatic bone tumor. A meta-analysis of studies using NSAIDs to treat bone pain did not demonstrate them to be more effective than weak opioids such as codeine, oxycodone and Recent data detailing cancer-related bone pain as a neuropathic pain model have challenged the dogma NSAIDs for bone pain.
Numerous studies have elucidated the major risk factors for GI toxicity, particularly ulcerative complications, associated with NSAIDs. These risk factors include advanced age, higher doses, concomitant administration of corticosteroids, and history of either ulcer disease or previous GI complications from NSAIDs the Various prophylactic therapies are administered prevention to ex- complications. Misoprostol is the only U.S. Food and Drug administration-approved medication for this indication Cochrane systematic review supports its use for prevention of NSAID-induced GI complications More commonly, p pump inhibitors are prescribed, which have been associated significantly decreased frequency of NSAID-related dyspepsia and fewer ulcers diagnosed by endoscopy. Whether this fewer GI bleeds and reduced health care utilization is still being debated. An empiric approach at this time is to administer misoprostol or a proton-pump inhibitor to all patients rec NSAIDs with significant risk factors for GI complication.
Nonopioid drugs represent the front-line approach for cancer pain management, but the choice and use of nonopioid need to be individualized. Although several NSAIDs have been use as approved by the U s. Food and Drug Administration for analgesics for mild to moderate pain (Table 64.1.9), guid for the use of NSAIDs in patients with cancer are largely empirical. According to a 2004 Cochrane review of 42 trials involving cancer pain patients, evidence demonstrared the at best a nonstatistically significant trents when NSAIDs trends toward improve and opioids were combined, were limited by the short duration The clinician must select an agent based on evidence, individual patient
history, and patient-specific considerations, and then must give the patient an adequate trial that nonopioid analgesic before switching to an alternative one. Such a trial should include administration of the drug to maximum levels at regular intervals. use there is a great variability among patient responses to different drugs, patients may require trials with several ore finding an effective drug and dose regimen. pain re- Kris not obtained, adding an opioid to a nonopioid provides additive analgesia. Combinations containing codeine, oxycodone, and propoxyphene are available, but these combinations often contain less man the full dose of 650 mg of aspirin or acetaminophen Prescribing each drug separately provides a better method for individualizing pain control; this is particularly important when patient requires escalation of the combination to provide analgesia, in which case the additional amount of the NSAID or acetaminophen may become excessive