Analgesics for osteoarthritis.

Evidence-Based Answer No differences in efficacy for pain and other symptoms of osteoarthritis have been found in direct comparisons of nonselective, selective, and partially selective nonsteroidal anti-inflammatory drugs (NSAIDs). Acetaminophen is modestly inferior to NSAIDs for pain relief. Among topical formulations, diclofenac is comparable to oral NSAIDs for treating localized osteoarthritis symptoms. Limited evidence from placebo comparisons shows benefits with topical capsaicin, but not with topical salicylates. Pharmaceuticalgrade glucosamine also has demonstrated some efficacy against osteoarthritic pain compared with placebo and NSAIDs; however, these findings may not apply to the unregulated products available in the United States, and the evidence is still unresolved. All NSAIDs have deleterious effects on blood pressure, edema, and kidney function. Risk of cardiovascular adverse effects is increased by nonselective and selective NSAIDs. Gastrointestinal (GI) adverse effects encountered with nonselective NSAIDs are further aggravated by low-dose aspirin and anticoagulants. Selective NSAIDs pose lower risks of GI complications than nonselective NSAIDs, but concomitant use of low-dose aspirin eliminates this benefit. GI adverse effects may be ameliorated with proton pump inhibitors or histamine H2 antagonists. None of the analgesics examined have shown greater benefits relative to adverse effects. Trade-offs between benefits and adverse effects differ across analgesics, increasing the need to consider individual patient priorities, age, comorbidities (e.g., preexisting GI bleeding, cardiovascular disease), and concomitant medications (e.g., low-dose aspirin and anticoagulants, prednisone) when choosing among these medications. (Strength of Recommendation: A, based on consistent, good-quality patientoriented evidence.)