[Switching from oral oxycodone to oxycodone injection - an investigation into the dosage amount ratio].

In switching from oraloxycodone to oxycodone injection, clinical guidelines recommend a conversion dose ratio of 0.75. However, in clinical sites, a higher dosage may be needed due to characteristics of cancer pain. In the present study, we investigated changing the dosage amount of oxycodone before and after switching from oraloxycodone administration to oxycodone injection in patients (n=14) who reported suffering from cancer pain. As a result, we found the ratio of the amount used after switching to be 0.91 ± 0.25 (mean ± SD) on the first day, increasing to 1.46 ± 0.48 on the fifth day. Our findings suggest that the dosage amount was the correct one for each patient's condition and also that adequate injection dosage to manage cancer pain was greater than that of calculated by the conversion ratio.