Challenging the equipotency calculation for transdermal buprenorphine: four case studies.

AIMS: Opioids produce analgesia via different pain pathways. The aim of these case studies was to address the issue of opioid rotation or switching, raising the important issue of conversion ratios between different compounds and routes of administration. RESULTS: We present two cases of neuropathic pain and two cases of nociceptive pain with a significant neuropathic component, which were successfully treated with transdermal buprenorphine after the failure of other opioids. CONCLUSION: In each case, effective pain relief was produced by a lower dose than the proposed equipotency ratio of 1:75 would indicate, suggesting that a ratio of 1:110 to 1:115 may be more appropriate.