Support of opioid rotation using online apps: Evaluation of applicability and comparison to the LONTS guidelines

Background: Opioid rotation can be indicated due to drug side effects, drug interactions or inadequate effect of treatment with opioids. For the determination of the oral morphine equivalence, a practice tool has been published with the long-term use of opioids in chronic nontumor-related pain (LONTS) guidelines. In contrast, several apps are available that have not yet been evaluated. Material and methods: Apps and web applications for opioid conversion were searched using Google Play Store®, iOS App Store® and the Google® search engine. German and English language apps with calculator functions were included. Using the apps, 16 test cases from clinical practice were calculated and the deviation from the recommendation of the LONTS guidelines was calculated. Results: A total of 17 apps were identified, 11 named the origin of the algorithm and 3 of them defined the literature sources. None of the apps and web applications had a quality seal, and none could solve all cases. Deviations of the resulting oral morphine equivalents of up to 179% from the guideline-compliant conversion were identified and 4 apps warned for overdosing. Conclusion: Although the apps and web applications simplify conversion between opioids, there is high variance in conversion factors and sometimes a relevant deviation from evidence-based tables. Overall, there is a high risk of false opioid dosing.