Abstract
Purpose: A case of effective pain control by opioid rotation from fentanyl patch (oral morphine:fentanyl=100: 1 ratio) was succeeded with less than the theoretically equivalent conversion dose. Therefore, an investigation was undertaken to determine the effective rotation dose from fentanyl patch to other opioids. Methods: Retrospective analysis was carried out on patients with cancer-related pain, who were switched from fentanyl patch to other opioids. Results: Fourteen patients were analyzed and the average effective dose of opioids after the rotation was 76% of the theoretically calculated dose. Effective doses after opioid rotation were less than calculated doses in 11 cases (79%) and more than calculated doses in only 3 cases (21%). Effective doses after opioid rotation were 101% of calculated doses in cases (n=5) with less than 75μg/hr of fentanyl patch, but 63% in cases (n=9) with more than 75μg/hr. Conclusion: Opioid rotation should be considered when administration of more than 75μg/hr of fentanyl patch is needed. It is necessary to reduce the amount of applied dose to approximately 60% of calculated dose for safe opioid rotation. Moreover, it is necessary to remain careful and to provide immediate assistance in case of emergency due to withdrawal syndrome. Palliat Care Res 2009; 5(1): 301-307
