A Retrospective Study on the Effectiveness of Switching to Oral Methadone for Relieving Severe Cancer-Related Neuropathic Pain and Limiting Adjuvant Analgesic Use in Japan.

Background: Cancer-related neuropathic pain is resistant to treatment with multiple medications and results in reduced patient quality of life.

Objective: The aim was to find a new curative to treat neuropathic pain without using adjuvant analgesics.

Design: This was a retrospective study that used the FACES Pain Scale (FPS) to measure pain intensity and pain relief.