For patients with OA of the hip and knee, chronic pain is typically managed according to ACR guidelines, as outlined in Figure 1 (ACR 2000 ). Acetaminophen is recommended as first-line therapy, although even doses up to 4 g may not provide sufficient pain relief (ACR 2000 ). Nonselective NSAIDs and COX-2 inhibitors are recommended for patients intolerant or unresponsive to acetaminophen (ACR 2000 ). The decision to prescribe nonselective NSAIDs is largely determined by a patient’s risk for upper gastrointestinal (GI) disorders following treatment with these agents. These include a history of peptic ulcer disease, increased GI bleeding, use of corticosteroids or anticoagulants (ACR 2000 ), and generally poor state of health (ACR 2000 ). Nonselective NSAIDs and COX-2 inhibitors can cause renal toxicity and should be used with caution in patients with mild to moderate renal insufficiency; these agents should not be used in patients with severe renal insufficiency (ACR 2000 ). Nonselective NSAIDs in combination with gastroprotective agents – misoprostol or a proton pump inhibitor – are recommended for patients unable to take either COX-2 inhibitors or nonselective NSAID monotherapy (ACR 2000 ). Patients susceptible to NSAID-induced platelet inhibition and bleeding may be prescribed nonacetylated salicylates (ACR 2000 ).
Tramadol is a centrally acting oral analgesic that blocks pain through opioid receptor binding and inhibition of norepinephrine and serotonin reuptake. It is currently indicated for the management of moderate to moderately severe pain in adults (Ultram PI 2004 ). Tramadol may be combined with NSAIDs in patients whose symptoms are poorly controlled by these agents (ACR 2000 ). Immediate-release (IR) tramadol is initiated at 25 mg and titrated in 25 mg increments over 3 days to achieve 25 mg four times daily (qid), then in 50 mg increments over 3 days to 50 mg qid (Ultram PI 2004 ). After titration, tramadol may be administered in doses of 50 mg to 100 mg every 4-6 hours as required for pain relief up to a daily maximum of 400 mg; the mean effective daily dosage is between 100 mg and 300 mg (Ultram PI 2004 ). The most common side effects of tramadol are dizziness, nausea, constipation, and drowsiness (Ultram PI 2004 ). Despite its mild opioid effects, tramadol has a low potential for abuse and remains the only unscheduled opioid (ACR 2000 ). More potent opioid therapy is recommended for patients unresponsive to or intolerant of tramadol (ACR 2000 ). Joint guidelines have been published by the American Pain Society and American Academy of Pain Medicine on the use of more potent opioids for the management of chronic, noncancer pain. Lifesaving and safe for many patients, a cautious approach with a careful risk assessment should be done in all patients taking opioids (ACR 2000 ).