Randomized study of tramadol/acetaminophen versus placebo in painful diabetic peripheral neuropathy

ABSTRACTObjective: To examine the efficacy and safety of tramadol/acetaminophen (APAP) for the management of painful diabetic peripheral neuropathy (DPN).Methods: Adults with painful DPN involving the lower extremities received 37.5 mg tramadol/325 mg APAP or placebo, up to 1–2 tablets four times daily, for 66 days. Subjects rated average daily pain and sleep interference from 0 (‘none’) to 10 (‘pain as bad as you can imagine’ or ‘complete interference’) every night. Baseline values were recorded for 7 days before starting study medication. The primary endpoint was change in mean of average daily pain scores from baseline to final week. Secondary efficacy outcomes included pain intensity, sleep interference, quality of life, mood, and global impression of change. Potential study limitations included permission to use serotonin reuptake inhibitors concomitantly (except venlafaxine or duloxetine) and the lack of a tramadol-alone or APAP-alone control group.Results: A total of 160 subjects received tramadol/...