[Indication and usage of opioids except morphine for chronic non-malignant intractable pain]

Indication and usage of opioids except morphine for chronic non-malignant intractable pain were reviewed. In Japan, other than morphine, we can use only two opioids, codeine phosphate (codeine), and dihydrocodeine phosphate (dihydrocodeine) for non-malignant pain management according to medical insurance system. But in western countries sustained-release opioids such as MS contine, transdermal fentanyl, oxycontin were used for the management of non-malignant chronic pain. The WHO ladder for cancer management should also be used for the management of non-malignant pain. Initial dose of codeine is 60 mg x day(-1) and the dosage should be increased or decreased according to pain intensity, patients' general condition and age. In most cases pain is controlled at the dose of 80-310 mg x day(-1). If pain intensity does not decrease or change, codeine should be changed to morphine. In our clinic, starting dose of codeine was 40-480 mg x day(-1) (average dose: 107.8 mg x day(-1)), maximum dose was 60-1280 mg x day (average dose: 310 mg x day(-1)). Average period for administration of codeine was 294.4 days. Dihydrocodeine has twice analgesic efficacy compared to codeine. The initial dose is the same as codeine. We hope that sustained release opioids such as transdermal fentanyl, oxycontin, tramadol etc will be used in Japan for management of non-malignant chronic pain in the near future.