RESUMO
Patients endure the switching of opioids from fentanyl patch to morphine injection to improve inadequate pain relief. We retrospectively examined the differences between the maintenance dose of morphine injection after switching, its estimated dose prior to switching, and some other factors. As a result, 8 out of 9 patients had pain control after switching. Also, patients who increased the dose of the fentanyl patch more than twice in a month before switching required a significantly lower maintenance dose for the estimated dose after switching (p < 0.05) than those who took less. In conclusion, switching opioids to morphine injection is very effective, both from the viewpoint of pain control and the reduction of the amount of opioids used for patients with poor pain control, who frequently increase their use of the fentanyl patch.