Tramadol Co-Administration with Oxycodone or Hydrocodone Increases Opioid Burden without Improving Postoperative Pain Control.

Tramadol is frequently co-prescribed with oxycodone or hydrocodone after surgery under the assumption that its dual mechanism of action provides an opioid-sparing benefit. However, evidence supporting this practice is limited and inconsistent. We conducted a secondary analysis of the multicenter IGNITE ADOPT-PGx pragmatic trial of patients undergoing elective surgery who were prescribed oxycodone alone (n = 317) versus tramadol + oxycodone (n = 96), or hydrocodone alone (n = 563) versus tramadol + hydrocodone (n = 42). Co-primary outcomes of this study were cumulative morphine milligram equivalents (MME) consumed during the 10 days following surgery and composite pain scores at day 10 defined as the sum of current pain and average and worst pain in the past 7 days (score ranges from 3 to 15). Inverse probability of treatment weighting (IPTW) was used to adjust for demographic characteristics, comorbidities, and concomitant analgesics. Sensitivity analyses restricted to CYP2D6 normal metabolizers and sites prescribing both monotherapy and combination therapy and subgroup analysis including total knee arthroplasty patients were conducted. Compared to oxycodone alone, the combination of oxycodone and tramadol was associated with higher MME (adjusted mean 205.2 vs 122.5; P < 0.0001) and lower mobility, without meaningful differences in pain scores (adjusted mean 9.6 vs 9.4; P = 0.41). Similar findings were observed for hydrocodone-only vs hydrocodone + tramadol groups. Results were consistent in sensitivity and subgroup analyses. Co-administration of tramadol with oxycodone or hydrocodone was associated with substantially higher total MME and reduced mobility without any demonstrable improvement in pain control.